Detecting triggering events for distributed denial of service attacks

ABSTRACT

An endpoint in an enterprise network is monitored, and when a potential trigger for a distributed denial of service (DDoS) attack is followed by an increase in network traffic from the endpoint to a high reputation network address, the endpoint is treated as a DDoS service bot and isolated from the network until remediation can be performed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/479,476 filed on Apr. 5, 2017, which is a continuation filed under 35U.S.C. § 111(a) that claims priority under 35 U.S.C. § 120 and § 365(c)to International Application No. PCT/US16/40094, filed Jun. 29, 2016,the entire contents of which are hereby incorporated herein byreference. U.S. patent application Ser. No. 15/479,476 is also acontinuation-in-part of each of U.S. patent application Ser. No.15/136,687 and U.S. patent application Ser. No. 15/136,762 (now U.S.Pat. No. 10,938,781), both filed on Apr. 22, 2016.

TECHNICAL FIELD

This application relates to techniques for improving security ofcommunications with endpoints in an enterprise network.

BACKGROUND

Enterprise networks can contain valuable information that forms anincreasingly attractive target for malicious actors. Useful techniquesfor securing endpoints in a network against malicious activity aredescribed by way of example in commonly-owned U.S. patent applicationSer. No. 14/263,955, filed on Apr. 28, 2014, U.S. application Ser. No.14/485,759, filed on Sep. 14, 2014, and U.S. patent application Ser. No.15/042,862 filed on Feb. 12, 2016, each of which is hereby incorporatedby reference in its entirety.

There remains a need for improved security of communications to and fromendpoints in an enterprise network.

SUMMARY

An endpoint in an enterprise network is monitored, and when a potentialtrigger for a distributed denial of service (DDoS) attack is followed byan increase in network traffic from the endpoint to a high reputationnetwork address, the endpoint is treated as a DDoS service bot andisolated from the network until remediation can be performed.

A computer program product for protecting against distributed denial ofservice attacks from an enterprise network may include computerexecutable code embodied in a non-transitory computer readable mediumthat, when executing on one or more computing devices, performs thesteps of monitoring outbound traffic from an endpoint in the enterprisenetwork, detecting a potential trigger event on the endpoint for adistributed denial of service attack, observing an increase in networktraffic from the endpoint directed to a high reputation network addressafter detecting the potential trigger event, in response to the increasein network traffic, identifying the endpoint as having a compromisedstate in which the endpoint serves as a distributed denial of servicebot for the distributed denial of service attack, and preventing networktraffic from the endpoint until the compromised state is remediated.

Implementations may include one or more of the following features. Thepotential trigger event may include a detection of a process on theendpoint that monitors a clock. The potential trigger event may includea detection of a process on the endpoint that monitors a file on theendpoint. The potential trigger event may include a detection of networktraffic between the endpoint and a low reputation network address. Thepotential trigger event may include a detection of network traffic froma command and control site. The potential trigger event may include adetection of an increase in network traffic to the high reputationnetwork address from one or more other endpoints in the enterprisenetwork. Monitoring the outbound traffic may include monitoring theoutbound traffic at a gateway for the enterprise network. Monitoring theoutbound traffic may include monitoring the outbound traffic at theendpoint.

A method may include monitoring outbound traffic from an endpoint in anenterprise network, detecting a potential trigger event for adistributed denial of service attack, observing an increase in networktraffic from the endpoint directed to a high reputation network addressafter detecting the potential trigger event, in response to the increasein network traffic, identifying the endpoint as having a compromisedstate wherein the endpoint serves as a distributed denial of servicebot, and preventing network traffic from the endpoint until thecompromised state is remediated.

Implementations may include one or more of the following features. Thepotential trigger event may include a detection of a process on theendpoint that monitors a clock. The potential trigger event may includea detection of a process on the endpoint that monitors a file on theendpoint. The potential trigger event may include a receipt of a messageon the endpoint from a low reputation network address. The potentialtrigger event may include a receipt of a message on the endpoint from acommand and control site. The potential trigger event may include adetection of an increase in network traffic to the high reputationnetwork address from one or more other endpoints in the enterprisenetwork. Monitoring the outbound traffic may include monitoring theoutbound traffic at a gateway for the enterprise network. Monitoring theoutbound traffic may include monitoring the outbound traffic at theendpoint. Observing an increase in network traffic may include observingan increase in network traffic beyond a predetermined threshold. Themethod may further include remediating the endpoint.

A threat management facility for managing an enterprise network mayinclude a network interface for coupling the threat management facilityto the enterprise network, a memory, and a processor. The processor maybe configured by computer executable code stored in the memory toprotect against a distributed denial of service attack originating fromwithin the enterprise network by performing the steps of monitoringoutbound traffic from an endpoint in the enterprise network, detecting apotential trigger event on the network for a distributed denial ofservice attack, observing an increase in network traffic from theendpoint directed to a high reputation network address after detectingthe potential trigger event, in response to the increase in networktraffic, identifying the endpoint as having a compromised state whereinthe endpoint serves as a distributed denial of service bot, andpreventing network traffic from the endpoint until the compromised stateis remediated. The processor may be further configured to initiate aremediation of the endpoint.

In the context of network activity by an endpoint in an enterprisenetwork, malware detection is improved by using a combination ofreputation information for a network address that is accessed by theendpoint with reputation information for an application on the endpointthat is accessing the network address. This information, when combinedwith a network usage history for the application, provides improveddifferentiation between malicious network activity and legitimate,user-initiated network activity.

A computer program product for protecting against malicious networkactivity in an enterprise network may include computer executable codeembodied in a non-transitory computer readable medium that, whenexecuting on one or more computing devices, performs the steps ofdetecting a connection from an application executing on an endpoint inthe enterprise network to a network address outside the enterprisenetwork, determining a reputation of the application using a firstreputation lookup at a threat management facility for the enterprisenetwork, determining a reputation of the network address using a secondreputation lookup at the threat management facility, determining anetwork usage history for the application using a log of networkactivity maintained on the endpoint, evaluating the endpoint for acompromised condition based on the reputation of the application, thereputation of the network address, and the network usage history for theapplication, and initiating remediation action on the endpoint when thecompromised condition is detected.

Implementations may include one or more of the following features. Thereputation of the application may include at least one of knownmalicious, suspect, unknown, or known good. The reputation of thenetwork address may include at least one of known malicious, suspect,unknown, or known good. The reputation of the network address may bebased on crowd-sourced information about the network address. Thecomputer program product may further include code that performs the stepof monitoring network activity by the application and storing thenetwork usage history for the application in the log on the endpoint.The computer program product may further include code that performs thestep of associating a network communication to the network address by aservice executing on the endpoint with the application when theapplication controls the network communication, and adding the networkcommunication to the network usage history for the application. The oneor more computing devices may include the endpoint. The one or morecomputing devices may include the threat management facility.

A method may include detecting a connection from an endpoint in anenterprise network to a network address, determining a reputation of anapplication using the connection, determining a reputation of thenetwork address, determining a network usage history for theapplication, evaluating the endpoint for a compromised condition basedon the reputation of the application, the reputation of the networkaddress, and the network usage history for the application, andinitiating remediation action on the endpoint when the compromisedcondition is detected.

Implementations may include one or more of the following features. Thereputation of the application may be requested from a threat managementfacility for the enterprise network. The reputation of the applicationmay include at least one of known malicious, suspect, unknown, or knowngood. The reputation of the network address may be requested from athreat management facility for the enterprise network. The reputation ofthe network address may include at least one of known malicious,suspect, unknown, or known good. The network usage history for theapplication may be retrieved from a log on the endpoint. The reputationof the network address may be based on crowd-sourced information aboutthe network address. The method may further include monitoring networkactivity by the application and storing the network usage history forthe application in a log on the endpoint. The method may further includeassociating a network communication to the network address by a serviceexecuting on the endpoint with the application when the applicationcontrols the network communication, and adding the network communicationto the network usage history for the application.

A threat management facility for managing an enterprise network mayinclude a network interface for coupling the threat management facilityto the enterprise network, a memory, and a processor configured bycomputer executable code stored in the memory to protect againstmalicious network activity in the enterprise network by performing thesteps of detecting a connection from an endpoint in an enterprisenetwork to a network address, determining a reputation of an applicationusing the connection, determining a reputation of the network address,determining a network usage history for the application, evaluating theendpoint for a compromised condition based on the reputation of theapplication, the reputation of the network address, and the networkusage history for the application, and initiating remediation action onthe endpoint when the compromised condition is detected. The reputationof the application may include at least one of known malicious, suspect,unknown, or known good, and the reputation of the network address mayinclude at least one of known malicious, suspect, unknown, or knowngood. The network usage history for the application may be retrievedfrom a log on the endpoint.

Protocol suites such as hypertext transfer protocol (HTTP) using securesocket layer (SSL) can facilitate secure network communications. Whenusing this type of secure communication, network addresses are typicallyexpressed as numeric internet protocol addresses rather than thehuman-readable uniform resource locators (URLs) that are entered into abrowser address bar by a human user. This property can be exploited todifferentiate between secure and insecure communications, and to detectcertain instances where a malicious proxy has been deployed to interceptnetwork traffic with an endpoint.

A computer program product for detecting a malicious proxy on anendpoint in an enterprise network may include computer executable codeembodied in a non-transitory computer readable medium that, whenexecuting on one or more computing devices, performs the steps ofmonitoring outbound traffic from the endpoint with remote networkaddresses outside the enterprise network, detecting use of a securecommunication protocol with a request from the endpoint to one of theremote network addresses, identifying a plaintext network address withinthe request, and, in response to identifying a plaintext network addressin the request, initiating remediation of a potentially malicious localproxy on the endpoint.

Implementations may include one or more of the following features. Thesecure communication protocol may include a hypertext transfer protocolusing secure socket layer or transport layer security. The plaintextnetwork address may include an alphanumeric address other than aninternet protocol address. The plaintext network address may include auniform resource locator. Monitoring outbound traffic may includelooking up a reputation for destinations of outbound communications.Monitoring outbound traffic may include monitoring outbound traffic at agateway for the enterprise network. Initiating remediation of thepotentially malicious local proxy may include quarantining the endpointuntil the potentially malicious local proxy can be removed. Initiatingremediation of the potentially malicious local proxy may includereversing a malware identification for the potentially malicious proxyby identifying a non-malicious source of the local proxy. Initiatingremediation of the potentially malicious local proxy may includeverifying a malware identification for the potentially malicious localproxy by performing the steps of identifying a process that initiatedthe request, determining a reputation of the process, if the reputationof the process is low or unknown, confirming the malware identification,and, if the reputation of the process is good, confirming the malwareidentification only when a calling process for the process that has alow or unknown reputation.

A method may include monitoring outbound traffic from an endpoint in anenterprise network, detecting use of a secure communication protocolwith a request from the endpoint, identifying a plaintext networkaddress within the request, and in response to identifying a plaintextnetwork address in the request, remediating a potentially maliciouslocal proxy on the endpoint.

Implementations may include one or more of the following features. Thesecure communication protocol may include a hypertext transfer protocolusing secure socket layer or transport layer security. The plaintextnetwork address may include an alphanumeric address other than aninternet protocol address. The plaintext network address may include auniform resource locator. Monitoring outbound traffic may includelooking up a reputation for destinations of outbound communications.Monitoring outbound traffic may include monitoring outbound traffic at agateway for the enterprise network. Initiating remediation of thepotentially malicious local proxy may include quarantining the endpointuntil the potentially malicious local proxy can be removed. Initiatingremediation of the potentially malicious local proxy may includereversing a malware identification for the potentially malicious proxyby identifying a non-malicious source of the local proxy. Initiatingremediation of the potentially malicious local proxy may includeverifying a malware identification for the potentially malicious localproxy by performing the steps of identifying a process that initiatedthe request, determining a reputation of the process, if the reputationof the process is low or unknown, confirming the malware identification,and, if the reputation of the process is good, confirming the malwareidentification only when a calling process for the process that has alow or unknown reputation.

A device may include a network interface, a memory, and a processor. Theprocessor may be configured by computer executable code stored in thememory to perform the steps of monitoring outbound traffic from anendpoint in an enterprise network, detecting use of a securecommunication protocol with a request from the endpoint, identifying aplaintext network address within the request, and in response toidentifying a plaintext network address in the request, remediating apotentially malicious local proxy on the endpoint. The securecommunication protocol may be a hypertext transfer protocol using securesocket layer or transport layer security.

BRIEF DESCRIPTION OF THE FIGURES

The foregoing and other objects, features and advantages of the devices,systems, and methods described herein will be apparent from thefollowing description of particular embodiments thereof, as illustratedin the accompanying drawings. The drawings are not necessarily to scale,emphasis instead being placed upon illustrating the principles of thedevices, systems, and methods described herein.

FIG. 1 illustrates an environment for threat management.

FIG. 2 illustrates a computer system.

FIG. 3 illustrates a threat management system.

FIG. 4 illustrates a system for behavioral tracking, coloring, andgeneration of indications of compromise (IOCs).

FIG. 5 illustrates a system for encryption management.

FIG. 6 illustrates a threat management system using heartbeats.

FIG. 7 shows an architecture for endpoint protection in an enterprisenetwork security system.

FIG. 8 shows a method for labeling network flows.

FIG. 9 illustrates an Internet Protocol packet.

FIG. 10 illustrates a method for secure labeling of network flows.

FIG. 11 shows a process for verifying user presence on an endpoint.

FIG. 12 shows a method for mitigating distributed denial of serviceattacks from an enterprise network.

FIG. 13 shows a method for detecting endpoint compromise based onnetwork usage history.

FIG. 14 shows useful malware detection insights based on the monitoringdescribed with reference to FIG. 13 .

FIG. 15 shows a method for local proxy detection.

DETAILED DESCRIPTION

Embodiments will now be described with reference to the accompanyingfigures, in which preferred embodiments are shown. The foregoing may,however, be embodied in many different forms and should not be construedas limited to the illustrated embodiments set forth herein.

All documents mentioned herein are hereby incorporated by reference intheir entirety. References to items in the singular should be understoodto include items in the plural, and vice versa, unless explicitly statedotherwise or clear from the context. Grammatical conjunctions areintended to express any and all disjunctive and conjunctive combinationsof conjoined clauses, sentences, words, and the like, unless otherwisestated or clear from the context. Thus, the term “or” should generallybe understood to mean “and/or” and so forth.

Recitation of ranges of values herein are not intended to be limiting,referring instead individually to any and all values falling within therange, unless otherwise indicated herein, and each separate value withinsuch a range is incorporated into the specification as if it wereindividually recited herein. The words “about,” “approximately,” or thelike, when accompanying a numerical value, are to be construed asindicating a deviation as would be appreciated by one of ordinary skillin the art to operate satisfactorily for an intended purpose. Ranges ofvalues and/or numeric values are provided herein as examples only, anddo not constitute a limitation on the scope of the describedembodiments. The use of any and all examples, or exemplary language(“e.g.,” “such as,” or the like) provided herein, is intended merely tobetter illuminate the embodiments and does not pose a limitation on thescope of the embodiments or the claims. No language in the specificationshould be construed as indicating any unclaimed element as essential tothe practice of the embodiments.

In the following description, it is understood that terms such as“first,” “second,” “third,” “above,” “below,” and the like, are words ofconvenience and are not to be construed as implying a chronologicalorder or otherwise limiting any corresponding element unless expresslystate otherwise.

FIG. 1 illustrates an environment for threat management. Specifically,FIG. 1 depicts a block diagram of a threat management system providingprotection to an enterprise against a plurality of threats—a context inwhich the following techniques may usefully be deployed. One aspectrelates to corporate policy management and implementation through aunified threat management facility 100. As will be explained in moredetail below, a threat management facility 100 may be used to protectcomputer assets from many threats, both computer-generated threats anduser-generated threats. The threat management facility 100 may bemulti-dimensional in that it may be designed to protect corporate assetsfrom a variety of threats and it may be adapted to learn about threatsin one dimension (e.g. worm detection) and apply the knowledge inanother dimension (e.g. spam detection). Policy management is one of thedimensions for which the threat management facility can provide acontrol capability. A corporation or other entity may institute a policythat prevents certain people (e.g. employees, groups of employees, typesof employees, guest of the corporation, etc.) from accessing certaintypes of computer programs. For example, the corporation may elect toprevent its accounting department from using a particular version of aninstant messaging service or all such services. In this example, thepolicy management facility 112 may be used to update the policies of allcorporate computing assets with a proper policy control facility or itmay update a select few. By using the threat management facility 100 tofacilitate the setting, updating and control of such policies thecorporation only needs to be concerned with keeping the threatmanagement facility 100 up to date on such policies. The threatmanagement facility 100 can take care of updating all of the othercorporate computing assets.

It should be understood that the threat management facility 100 mayprovide multiple services, and policy management may be offered as oneof the services. We will now turn to a description of certaincapabilities and components of the threat management system 100.

Over recent years, malware has become a major problem across theInternet 154. From both a technical perspective and a user perspective,the categorization of a specific threat type, whether as virus, worm,spam, phishing exploration, spyware, adware, or the like, is becomingreduced in significance. The threat, no matter how it is categorized,may need to be stopped at various points of a networked computingenvironment, such as one of an enterprise facility 102, including at oneor more laptops, desktops, servers, gateways, communication ports,handheld or mobile devices, firewalls, and the like. Similarly, theremay be less and less benefit to the user in having different solutionsfor known and unknown threats. As such, a consolidated threat managementfacility 100 may need to apply a similar set of technologies andcapabilities for all threats. In certain embodiments, the threatmanagement facility 100 may provide a single agent on the desktop, and asingle scan of any suspect file. This approach may eliminate theinevitable overlaps and gaps in protection caused by treating virusesand spyware as separate problems, while simultaneously simplifyingadministration and minimizing desktop load. As the number and range oftypes of threats has increased, so may have the level of connectivityavailable to all IT users. This may have led to a rapid increase in thespeed at which threats may move. Today, an unprotected PC connected tothe Internet 154 may be infected quickly (perhaps within 10 minutes)which may require acceleration for the delivery of threat protection.Where once monthly updates may have been sufficient, the threatmanagement facility 100 may automatically and seamlessly update itsproduct set against spam and virus threats quickly, for instance, everyfive minutes, every minute, continuously, or the like. Analysis andtesting may be increasingly automated, and also may be performed morefrequently; for instance, it may be completed in 15 minutes, and may doso without compromising quality. The threat management facility 100 mayalso extend techniques that may have been developed for virus andmalware protection, and provide them to enterprise facility 102 networkadministrators to better control their environments. In addition tostopping malicious code, the threat management facility 100 may providepolicy management that may be able to control legitimate applications,such as VoIP, instant messaging, peer-to-peer file-sharing, and thelike, that may undermine productivity and network performance within theenterprise facility 102.

The threat management facility 100 may provide an enterprise facility102 protection from computer-based malware, including viruses, spyware,adware, Trojans, intrusion, spam, policy abuse, uncontrolled access, andthe like, where the enterprise facility 102 may be any entity with anetworked computer-based infrastructure. In an embodiment, FIG. 1 maydepict a block diagram of the threat management facility 100 providingprotection to an enterprise against a plurality of threats. Theenterprise facility 102 may be corporate, commercial, educational,governmental, or the like, and the enterprise facility's 102 computernetwork may be distributed amongst a plurality of facilities, and in aplurality of geographical locations, and may include administration 134,a firewall 138A, an appliance 140A, server 142A, network devices 148A-B,clients 144A-D, such as protected by computer security facilities 152,and the like. It will be understood that any reference herein to clientfacilities may include the clients 144A-D shown in FIG. 1 andvice-versa. The threat management facility 100 may include a pluralityof functions, such as security management facility 122, policymanagement facility 112, update facility 120, definitions facility 114,network access rules facility 124, remedial action facility 128,detection techniques facility 130, testing facility 118, threat researchfacility 132, and the like. In embodiments, the threat protectionprovided by the threat management facility 100 may extend beyond thenetwork boundaries of the enterprise facility 102 to include clients144D (or client facilities) that have moved into network connectivitynot directly associated or controlled by the enterprise facility 102.Threats to client facilities may come from a plurality of sources, suchas from network threats 104, physical proximity threats 110, secondarylocation threats 108, and the like. Clients 144A-D may be protected fromthreats even when the client 144A-D is not located in association withthe enterprise 102, such as when a client 144E-F moves in and out of theenterprise facility 102, for example when interfacing with anunprotected server 142C through the Internet 154, when a client 144F ismoving into a secondary location threat 108 such as interfacing withcomponents 140B, 142B, 148C, 148D that are not protected, and the like.In embodiments, the threat management facility 100 may provide anenterprise facility 102 protection from a plurality of threats tomultiplatform computer resources in a plurality of locations and networkconfigurations, with an integrated system approach. It should beunderstood that an enterprise model is applicable to organizations andusers of any size or type. For example, an enterprise may be or mayinclude a group or association of endpoints, networks, users, and thelike within or outside of one or more protected locations. It should beunderstood that an enterprise may include one or more offices orbusiness locations, or one or more homes, where each location, orportions of each location, or a collection of locations may be treatedas a client facility.

In embodiments, the threat management facility 100 may be provided as astand-alone solution. In other embodiments, the threat managementfacility 100 may be integrated into a third-party product. Anapplication programming interface (e.g. a source code interface) may beprovided such that the threat management facility 100 may be integrated.For instance, the threat management facility 100 may be stand-alone inthat it provides direct threat protection to an enterprise or computerresource, where protection is subscribed to directly 100. Alternatively,the threat management facility 100 may offer protection indirectly,through a third-party product, where an enterprise may subscribe toservices through the third-party product, and threat protection to theenterprise may be provided by the threat management facility 100 throughthe third-party product.

The security management facility 122 may include a plurality of elementsthat provide protection from malware to enterprise facility 102 computerresources, including endpoint security and control, email security andcontrol, web security and control, reputation-based filtering, controlof unauthorized users, control of guest and non-compliant computers, andthe like. The security management facility 122 may be a softwareapplication that may provide malicious code and malicious applicationprotection to a client facility computing resource. The securitymanagement facility 122 may have the ability to scan the client facilityfiles for malicious code, remove or quarantine certain applications andfiles, prevent certain actions, perform remedial actions and performother security measures. In embodiments, scanning the client facilitymay include scanning some or all of the files stored to the clientfacility on a periodic basis, scanning an application when theapplication is executed, scanning files as the files are transmitted toor from the client facility, or the like. The scanning of theapplications and files may be performed to detect known malicious codeor known unwanted applications. In an embodiment, new malicious code andunwanted applications may be continually developed and distributed, andupdates to the known code database may be provided on a periodic basis,on a demand basis, on an alert basis, or the like.

The security management facility 122 may provide email security andcontrol, where security management may help to eliminate spam, viruses,spyware and phishing, control of email content, and the like. Thesecurity management facility's 122 email security and control mayprotect against inbound and outbound threats, protect emailinfrastructure, prevent data leakage, provide spam filtering, and thelike. In an embodiment, security management facility 122 may provide forweb security and control, where security management may help to detector block viruses, spyware, malware, unwanted applications, help controlweb browsing, and the like, which may provide comprehensive web accesscontrol enabling safe, productive web browsing. Web security and controlmay provide Internet use policies, reporting on suspect devices,security and content filtering, active monitoring of network traffic,URI filtering, and the like. In an embodiment, the security managementfacility 122 may provide for network access control, which may providecontrol over network connections. Network control may stop unauthorized,guest, or non-compliant systems from accessing networks, and may controlnetwork traffic that may not be bypassed from the client level. Inaddition, network access control may control access to virtual privatenetworks (VPN), where VPNs may be a communications network tunneledthrough another network, establishing a logical connection acting as avirtual network. In embodiments, a VPN may be treated in the same manneras a physical network.

The security management facility 122 may provide host intrusionprevention through behavioral based protection, which may guard againstunknown threats by analyzing behavior before software code executes.Behavioral based protection may monitor code when it runs and interveneif the code is deemed to be suspicious or malicious. Advantages ofbehavioral based protection over runtime protection may include codebeing prevented from running. Whereas runtime protection may onlyinterrupt code that has already partly executed, behavioral protectioncan identify malicious code at the gateway or on the file servers anddelete the code before it can reach endpoint computers and the like.

The security management facility 122 may provide reputation filtering,which may target or identify sources of known malware. For instance,reputation filtering may include lists of URIs of known sources ofmalware or known suspicious IP addresses, or domains, say for spam, thatwhen detected may invoke an action by the threat management facility100, such as dropping them immediately. By dropping the source beforeany interaction can initiate, potential threat sources may be thwartedbefore any exchange of data can be made.

In embodiments, information may be sent from the enterprise back to athird party, a vendor, or the like, which may lead to improvedperformance of the threat management facility 100. For example, thetypes, times, and number of virus interactions that a client experiencesmay provide useful information for the preventions of future virusthreats. This type of feedback may be useful for any aspect of threatdetection. Feedback of information may also be associated with behaviorsof individuals within the enterprise, such as being associated with mostcommon violations of policy, network access, unauthorized applicationloading, unauthorized external device use, and the like. In embodiments,this type of information feedback may enable the evaluation or profilingof client actions that are violations of policy that may provide apredictive model for the improvement of enterprise policies.

The security management facility 122 may support overall security of theenterprise facility 102 network or set of enterprise facility 102networks, e.g., by providing updates of malicious code information tothe enterprise facility 102 network and associated client facilities.The updates may include a planned update, an update in reaction to athreat notice, an update in reaction to a request for an update, anupdate based on a search of known malicious code information, or thelike. The administration facility 134 may provide control over thesecurity management facility 122 when updates are performed. The updatesmay be automatically transmitted without an administration facility's134 direct control, manually transmitted by the administration facility134, or otherwise distributed. The security management facility 122 maymanage the receipt of malicious code descriptions from a provider,distribution of the malicious code descriptions to enterprise facility102 networks, distribution of the malicious code descriptions to clientfacilities, and so forth.

The threat management facility 100 may provide a policy managementfacility 112 that may be able to block non-malicious applications, suchas VoIP, instant messaging, peer-to-peer file-sharing, and the like,that may undermine productivity and network performance within theenterprise facility 102. The policy management facility 112 may be a setof rules or policies that may indicate enterprise facility 102 accesspermissions for the client facility, such as access permissionsassociated with the network, applications, external computer devices,and the like. The policy management facility 112 may include a database,a text file, a combination of databases and text files, or the like. Inan embodiment, a policy database may be a block list, a black list, anallowed list, a white list, or the like that may provide a list ofenterprise facility 102 external network locations/applications that mayor may not be accessed by the client facility. The policy managementfacility 112 may include rules that may be interpreted with respect toan enterprise facility 102 network access request to determine if therequest should be allowed. The rules may provide a generic rule for thetype of access that may be granted. The rules may be related to thepolicies of an enterprise facility 102 for access rights for theenterprise facility's 102 client facility. For example, there may be arule that does not permit access to sporting websites. When a website isrequested by the client facility, a security facility may access therules within a policy facility to determine if the requested access isrelated to a sporting website. In an embodiment, the security facilitymay analyze the requested website to determine if the website matcheswith any of the policy facility rules.

The policy management facility 112 may be similar to the securitymanagement facility 122 but with the addition of enterprise facility 102wide access rules and policies that may be distributed to maintaincontrol of client facility access to enterprise facility 102 networkresources. The policies may be defined for application type, subset ofapplication capabilities, organization hierarchy, computer facilitytype, user type, network location, time of day, connection type, or thelike. Policies may be maintained by the administration facility 134,through the threat management facility 100, in association with a thirdparty, or the like. For example, a policy may restrict IM activity toonly support personnel for communicating with customers. This may allowcommunication for departments requiring access, but may maintain thenetwork bandwidth for other activities by restricting the use of IM toonly the personnel that need access to instant messaging (IM) in supportof the enterprise facility 102. In an embodiment, the policy managementfacility 112 may be a stand-alone application, may be part of thenetwork server facility 142, may be part of the enterprise facility 102network, may be part of the client facility, or the like.

The threat management facility 100 may provide configuration management,which may be similar to policy management, but may specifically examinethe configuration set of applications, operating systems, hardware, andthe like, and manage changes to their configurations. Assessment of aconfiguration may be made against a standard configuration policy,detection of configuration changes, remediation of improperconfiguration, application of new configurations, and the like. Anenterprise may keep a set of standard configuration rules and policieswhich may represent the desired state of the device. For example, aclient firewall may be running and installed, but in the disabled state,where remediation may be to enable the firewall. In another example, theenterprise may set a rule that disallows the use of USB disks, and sendsa configuration change to all clients, which turns off USB drive accessvia a registry.

The threat management facility 100 may also provide for the removal ofapplications that potentially interfere with the operation of the threatmanagement facility 100, such as competitor products that may also beattempting similar threat management functions. The removal of suchproducts may be initiated automatically whenever such products aredetected. In the case where such applications are services are providedindirectly through a third-party product, the application may besuspended until action is taken to remove or disable the third-partyproduct's protection facility.

Threat management against a quickly evolving malware environment mayrequire timely updates, and thus an update management facility 120 maybe provided by the threat management facility 100. In addition, a policymanagement facility 112 may also require update management (e.g., asprovided by the update facility 120 herein described). The updatemanagement for the security facility 122 and policy management facility112 may be provided directly by the threat management facility 100, suchas by a hosted system or in conjunction with the administration facility134. In embodiments, the threat management facility 100 may provide forpatch management, where a patch may be an update to an operating system,an application, a system tool, or the like, where one of the reasons forthe patch is to reduce vulnerability to threats.

The security facility 122 and policy management facility 112 may pushinformation to the enterprise facility 102 network and/or clientfacility. The enterprise facility 102 network and/or client facility mayalso or instead pull information from the security facility 122 andpolicy management facility 112 network server facilities 142, or theremay be a combination of pushing and pulling of information between thesecurity facility 122 and the policy management facility 112 networkservers 142, enterprise facility 102 network, and client facilities, orthe like. For example, the enterprise facility 102 network and/or clientfacility may pull information from the security facility 122 and policymanagement facility 112 network server facility 142 may request theinformation using the security facility 122 and policy managementfacility 112 update module; the request may be based on a certain timeperiod, by a certain time, by a date, on demand, or the like. In anotherexample, the security facility 122 and policy management facility 112network servers 142 may push the information to the enterprisefacility's 102 network and/or client facility by providing notificationthat there are updates available for download and then transmitting theinformation. The combination of the security management 122 networkserver facility 142 and security update module may functionsubstantially the same as the policy management facility 112 networkserver and policy update module by providing information to theenterprise facility 102 network and the client facility in a push orpull method. In an embodiment, the policy management facility 112 andthe security facility 122 management update modules may work in concertto provide information to the enterprise facility's 102 network and/orclient facility for control of application execution. In an embodiment,the policy update module and security update module may be combined intoa single update module.

As threats are identified and characterized, the threat managementfacility 100 may create definition updates that may be used to allow thethreat management facility 100 to detect and remediate the latestmalicious software, unwanted applications, configuration and policychanges, and the like. The threat definition facility 114 may containthreat identification updates, also referred to as definition files. Adefinition file may be a virus identity file that may includedefinitions of known or potential malicious code. The virus identity(IDE) definition files may provide information that may identifymalicious code within files, applications, or the like. The definitionfiles may be accessed by security management facility 122 when scanningfiles or applications within the client facility for the determinationof malicious code that may be within the file or application. Thedefinition files may contain a number of commands, definitions, orinstructions, to be parsed and acted upon, or the like. In embodiments,the client facility may be updated with new definition filesperiodically to provide the client facility with the most recentmalicious code definitions; the updating may be performed on a set timeperiod, may be updated on demand from the client facility, may beupdated on demand from the network, may be updated on a receivedmalicious code alert, or the like. In an embodiment, the client facilitymay request an update to the definition files from an update facility120 within the network, may request updated definition files from acomputing facility external to the network, updated definition files maybe provided to the client facility 114 from within the network,definition files may be provided to the client facility from an externalcomputing facility from an external network, or the like.

A definition management facility 114 may provide timely updates ofdefinition files information to the network, client facilities, and thelike. New and altered malicious code and malicious applications may becontinually created and distributed to networks worldwide. Thedefinition files that maintain the definitions of the malicious code andmalicious application information for the protection of the networks andclient facilities may need continual updating to provide continualdefense of the network and client facility from the malicious code andmalicious applications. The definition files management may provide forautomatic and manual methods of updating the definition files. Inembodiments, the network may receive definition files and distribute thedefinition files to the network client facilities, the client facilitiesmay receive the definition files directly, or the network and clientfacilities may both receive the definition files, or the like. In anembodiment, the definition files may be updated on a fixed periodicbasis, on demand by the network and/or the client facility, as a resultof an alert of a new malicious code or malicious application, or thelike. In an embodiment, the definition files may be released as asupplemental file to an existing definition files to provide for rapidupdating of the definition files.

In a similar manner, the security management facility 122 may be used toscan an outgoing file and verify that the outgoing file is permitted tobe transmitted per the enterprise facility 102 rules and policies. Bychecking outgoing files, the security management facility 122 may beable discover malicious code infected files that were not detected asincoming files as a result of the client facility having been updatedwith either new definition files or policy management facility 112information. The definition files may discover the malicious codeinfected file by having received updates of developing malicious codefrom the administration facility 134, updates from a definition filesprovider, or the like. The policy management facility 112 may discoverthe malicious code infected file by having received new updates from theadministration facility 134, from a rules provider, or the like.

The threat management facility 100 may provide controlled access to theenterprise facility 102 networks. For instance, a manager of theenterprise facility 102 may want to restrict access to certainapplications, networks, files, printers, servers, databases, or thelike. In addition, the manager of the enterprise facility 102 may wantto restrict user access based on certain criteria, such as the user'slocation, usage history, need to know, job position, connection type,time of day, method of authentication, client-system configuration, orthe like. Network access rules may be developed for the enterprisefacility 102, or pre-packaged by a supplier, and managed by the threatmanagement facility 100 in conjunction with the administration facility134.

A network access rules facility 124 may be responsible for determiningif a client facility application should be granted access to a requestednetwork location. The network location may be on the same network as thefacility or may be on another network. In an embodiment, the networkaccess rules facility 124 may verify access rights for client facilitiesfrom within the network or may verify access rights of computerfacilities from external networks. When network access for a clientfacility is denied, the network access rules facility 124 may send aninformation file to the client facility containing. For example, theinformation sent by the network access rules facility 124 may be a datafile. The data file may contain a number of commands, definitions,instructions, or the like to be parsed and acted upon through theremedial action facility 128, or the like. The information sent by thenetwork access facility rules facility 124 may be a command or commandfile that the remedial action facility 128 may access and take actionupon.

The network access rules facility 124 may include databases such as ablock list, a black list, an allowed list, a white list, an unacceptablenetwork site database, an acceptable network site database, a networksite reputation database, or the like of network access locations thatmay or may not be accessed by the client facility. Additionally, thenetwork access rules facility 124 may incorporate rule evaluation; therule evaluation may parse network access requests and apply the parsedinformation to network access rules. The network access rule facility124 may have a generic set of rules that may be in support of anenterprise facility's 102 network access policies, such as denyingaccess to certain types of websites, controlling instant messengeraccesses, or the like. Rule evaluation may include regular expressionrule evaluation, or other rule evaluation method for interpreting thenetwork access request and comparing the interpretation to theestablished rules for network access. In an embodiment, the networkaccess rules facility 124 may receive a rules evaluation request fromthe network access control and may return the rules evaluation to thenetwork access control.

Similar to the threat definitions facility 114, the network access rulefacility 124 may provide updated rules and policies to the enterprisefacility 102. The network access rules facility 124 may be maintained bythe network administration facility 134, using network access rulesfacility 124 management. In an embodiment, the network administrationfacility 134 may be able to maintain a set of access rules manually byadding rules, changing rules, deleting rules, or the like. Additionally,the administration facility 134 may retrieve predefined rule sets from aremote provider of a set of rules to be applied to an entire enterprisefacility 102. The network administration facility 134 may be able tomodify the predefined rules as needed for a particular enterprisefacility 102 using the network access rules management facility 124.

When a threat or policy violation is detected by the threat managementfacility 100, the threat management facility 100 may perform or initiatea remedial action facility 128. Remedial action may take a plurality offorms, such as terminating or modifying an ongoing process orinteraction, sending a warning to a client or administration facility134 of an ongoing process or interaction, executing a program orapplication to remediate against a threat or violation, recordinteractions for subsequent evaluation, or the like. Remedial action maybe associated with an application that responds to information that aclient facility network access request has been denied. In anembodiment, when the data file is received, remedial action may parsethe data file, interpret the various aspects of the data file, and acton the parsed data file information to determine actions to be taken onan application requesting access to a denied network location. In anembodiment, when the data file is received, remedial action may accessthe threat definitions to parse the data file and determine an action tobe taken on an application requesting access to a denied networklocation. In an embodiment, the information received from the facilitymay be a command or a command file. The remedial action facility maycarry out any commands that are received or parsed from a data file fromthe facility without performing any interpretation of the commands. Inan embodiment, the remedial action facility may interact with thereceived information and may perform various actions on a clientrequesting access to a denied network location. The action may be one ormore of continuing to block all requests to a denied network location, amalicious code scan on the application, a malicious code scan on theclient facility, quarantine of the application, terminating theapplication, isolation of the application, isolation of the clientfacility to a location within the network that restricts network access,blocking a network access port from a client facility, reporting theapplication to an administration facility 134, or the like.

Remedial action may be provided as a result of a detection of a threator violation. The detection techniques facility 130 may includemonitoring the enterprise facility 102 network or endpoint devices, suchas by monitoring streaming data through the gateway, across the network,through routers and hubs, and the like. The detection techniquesfacility 130 may include monitoring activity and stored files oncomputing facilities, such as on server facilities 142, desktopcomputers, laptop computers, other mobile computing devices, and thelike. Detection techniques, such as scanning a computer's stored files,may provide the capability of checking files for stored threats, eitherin the active or passive state. Detection techniques, such as streamingfile management, may provide the capability of checking files receivedat the network, gateway facility, client facility, and the like. Thismay provide the capability of not allowing a streaming file or portionsof the streaming file containing malicious code from entering the clientfacility, gateway facility, or network. In an embodiment, the streamingfile may be broken into blocks of information, and a plurality of virusidentities may be used to check each of the blocks of information formalicious code. In an embodiment, any blocks that are not determined tobe clear of malicious code may not be delivered to the client facility,gateway facility, or network.

Verifying that the threat management facility 100 is detecting threatsand violations to established policy, may require the ability to testthe system, either at the system level or for a particular computingcomponent. The testing facility 118 may allow the administrationfacility 134 to coordinate the testing of the security configurations ofclient facility computing facilities on a network. The administrationfacility 134 may be able to send test files to a set of client facilitycomputing facilities to test the ability of the client facility todetermine acceptability of the test file. After the test file has beentransmitted, a recording facility may record the actions taken by theclient facility in reaction to the test file. The recording facility mayaggregate the testing information from the client facility and reportthe testing information to the administration facility 134. Theadministration facility 134 may be able to determine the level ofpreparedness of the client facility computing facilities by the reportedinformation. Remedial action may be taken for any of the client facilitycomputing facilities as determined by the administration facility 134;remedial action may be taken by the administration facility 134 or bythe user of the client facility.

The threat research facility 132 may provide a continuously ongoingeffort to maintain the threat protection capabilities of the threatmanagement facility 100 in light of continuous generation of new orevolved forms of malware. Threat research may include researchers andanalysts working on known and emerging malware, such as viruses,rootkits a spyware, as well as other computer threats such as phishing,spam, scams, and the like. In embodiments, through threat research, thethreat management facility 100 may be able to provide swift, globalresponses to the latest threats.

The threat management facility 100 may provide threat protection to theenterprise facility 102, where the enterprise facility 102 may include aplurality of networked components, such as client facility, serverfacility 142, administration facility 134, firewall 138, gateway, hubsand routers 148, threat management appliance 140, desktop users, mobileusers, and the like. In embodiments, it may be the endpoint computersecurity facility 152, located on a computer's desktop, which mayprovide threat protection to a user, and associated enterprise facility102. In embodiments, the term endpoint may refer to a computer systemthat may source data, receive data, evaluate data, buffer data, or thelike (such as a user's desktop computer as an endpoint computer), afirewall as a data evaluation endpoint computer system, a laptop as amobile endpoint computer, a personal digital assistant or tablet as ahand-held endpoint computer, a mobile phone as an endpoint computer, orthe like. In embodiments, endpoint may refer to a source or destinationfor data, including such components where the destination ischaracterized by an evaluation point for data, and where the data may besent to a subsequent destination after evaluation. The endpoint computersecurity facility 152 may be an application loaded onto the computerplatform or computer support component, where the application mayaccommodate the plurality of computer platforms and/or functionalrequirements of the component. For instance, a client facility computermay be one of a plurality of computer platforms, such as Windows,Macintosh, Linux, and the like, where the endpoint computer securityfacility 152 may be adapted to the specific platform, while maintaininga uniform product and product services across platforms. Additionally,components may have different functions to serve within the enterprisefacility's 102 networked computer-based infrastructure. For instance,computer support components provided as hubs and routers 148, serverfacility 142, firewalls 138, and the like, may require unique securityapplication software to protect their portion of the systeminfrastructure, while providing an element in an integrated threatmanagement system that extends out beyond the threat management facility100 to incorporate all computer resources under its protection.

The enterprise facility 102 may include a plurality of client facilitycomputing platforms on which the endpoint computer security facility 152is adapted. A client facility computing platform may be a computersystem that is able to access a service on another computer, such as aserver facility 142, via a network. This client facility server facility142 model may apply to a plurality of networked applications, such as aclient facility connecting to an enterprise facility 102 applicationserver facility 142, a web browser client facility connecting to a webserver facility 142, an e-mail client facility retrieving e-mail from anInternet 154 service provider's mail storage servers 142, and the like.In embodiments, traditional large client facility applications may beswitched to websites, which may increase the browser's role as a clientfacility. Clients 144 may be classified as a function of the extent towhich they perform their own processing. For instance, client facilitiesare sometimes classified as a fat client facility or thin clientfacility. The fat client facility, also known as a thick client facilityor rich client facility, may be a client facility that performs the bulkof data processing operations itself, and does not necessarily rely onthe server facility 142. The fat client facility may be most common inthe form of a personal computer, where the personal computer may operateindependent of any server facility 142. Programming environments for fatclients 144 may include CURI, Delphi, Droplets, Java, win32, X11, andthe like. Thin clients 144 may offer minimal processing capabilities,for instance, the thin client facility may primarily provide a graphicaluser interface provided by an application server facility 142, which mayperform the bulk of any required data processing. Programmingenvironments for thin clients 144 may include JavaScript/AJAX, ASP, JSP,Ruby on Rails, Python's Django, PHP, and the like. The client facilitymay also be a mix of the two, such as processing data locally, butrelying on a server facility 142 for data storage. As a result, thishybrid client facility may provide benefits from both the fat clientfacility type, such as multimedia support and high performance, and thethin client facility type, such as high manageability and flexibility.In embodiments, the threat management facility 100, and associatedendpoint computer security facility 152, may provide seamless threatprotection to the plurality of clients 144, and client facility types,across the enterprise facility 102.

The enterprise facility 102 may include a plurality of server facilities142, such as application servers, communications servers, file servers,database servers, proxy servers, mail servers, fax servers, gameservers, web servers, and the like. A server facility 142, which mayalso be referred to as a server facility 142 application, serverfacility 142 operating system, server facility 142 computer, or thelike, may be an application program or operating system that acceptsclient facility connections in order to service requests from clients144. The server facility 142 application may run on the same computer asthe client facility using it, or the server facility 142 and the clientfacility may be running on different computers and communicating acrossthe network. Server facility 142 applications may be divided amongserver facility 142 computers, with the dividing depending upon theworkload. For instance, under light load conditions all server facility142 applications may run on a single computer and under heavy loadconditions a single server facility 142 application may run on multiplecomputers. In embodiments, the threat management facility 100 mayprovide threat protection to server facilities 142 within the enterprisefacility 102 as load conditions and application changes are made.

A server facility 142 may also be an appliance facility 140, where theappliance facility 140 provides specific services onto the network.Though the appliance facility 140 is a server facility 142 computer,that may be loaded with a server facility 142 operating system andserver facility 142 application, the enterprise facility 102 user maynot need to configure it, as the configuration may have been performedby a third party. In an embodiment, an enterprise facility 102 appliancemay be a server facility 142 appliance that has been configured andadapted for use with the threat management facility 100, and locatedwithin the facilities of the enterprise facility 102. The enterprisefacility's 102 threat management appliance may enable the enterprisefacility 102 to administer an on-site local managed threat protectionconfiguration, where the administration facility 134 may access thethreat resources through an interface, such as a web portal. In analternate embodiment, the enterprise facility 102 may be managedremotely from a third party, vendor, or the like, without an appliancefacility 140 located within the enterprise facility 102. In thisinstance, the appliance functionality may be a shared hardware productbetween pluralities of enterprises 102. In embodiments, the appliancefacility 140 may be located at the enterprise facility 102, where theenterprise facility 102 maintains a degree of control. In embodiments, ahosted service may be provided, where the appliance 140 may still be anon-site black box to the enterprise facility 102, physically placedthere because of infrastructure requirements, but managed by a thirdparty, vendor, or the like.

Simple server facility 142 appliances may also be utilized across theenterprise facility's 102 network infrastructure, such as switches,routers, wireless routers, hubs and routers, gateways, print servers,net modems, and the like. These simple server facility appliances maynot require configuration by the enterprise facility 102, but mayrequire protection from threats via an endpoint computer securityfacility 152. These appliances may provide interconnection serviceswithin the enterprise facility 102 network, and therefore may advancethe spread of a threat if not properly protected.

A client facility may be protected from threats from within theenterprise facility 102 network using a personal firewall, which may bea hardware firewall, software firewall, or combination of these, thatcontrols network traffic to and from a client. The personal firewall maypermit or deny communications based on a security policy. Personalfirewalls may be designed for use by end-users, which may result inprotection for only the computer on which it's installed. Personalfirewalls may be able to control network traffic by providing promptseach time a connection is attempted and adapting security policyaccordingly. Personal firewalls may also provide some level of intrusiondetection, which may allow the software to terminate or blockconnectivity where it suspects an intrusion is being attempted. Otherfeatures that may be provided by a personal firewall may include alertsabout outgoing connection attempts, control of program access tonetworks, hiding the client from port scans by not responding tounsolicited network traffic, monitoring of applications that may belistening for incoming connections, monitoring and regulation ofincoming and outgoing network traffic, prevention of unwanted networktraffic from installed applications, reporting applications that makeconnection attempts, reporting destination servers with whichapplications may be attempting communications, and the like. Inembodiments, the personal firewall may be provided by the threatmanagement facility 100.

Another important component that may be protected by an endpointcomputer security facility 152 is a network firewall facility 138, whichmay be a hardware or software device that may be configured to permit,deny, or proxy data through a computer network that has different levelsof trust in its source of data. For instance, an internal enterprisefacility 102 network may have a high level of trust, because the sourceof all data has been sourced from within the enterprise facility 102. Anexample of a low level of trust is the Internet 154, because the sourceof data may be unknown. A zone with an intermediate trust level,situated between the Internet 154 and a trusted internal network, may bereferred to as a “perimeter network.” Since firewall facilities 138represent boundaries between threat levels, the endpoint computersecurity facility 152 associated with the firewall facility 138 mayprovide resources that may control the flow of threats at thisenterprise facility 102 network entry point. Firewall facilities 138,and associated endpoint computer security facility 152, may also beassociated with a network node that may be equipped for interfacingbetween networks that use different protocols. In embodiments, theendpoint computer security facility 152 may provide threat protection ina plurality of network infrastructure locations, such as at theenterprise facility 102 network entry point, i.e. the firewall facility138 or gateway; at the server facility 142; at distribution pointswithin the network, i.e. the hubs and routers 148; at the desktop ofclient facility computers; and the like. In embodiments, the mosteffective location for threat detection may be at the user's computerdesktop endpoint computer security facility 152.

The interface between the threat management facility 100 and theenterprise facility 102, and through the appliance facility 140 toembedded endpoint computer security facilities, may include a set oftools that may be the same for all enterprise implementations, but alloweach enterprise to implement different controls. In embodiments, thesecontrols may include both automatic actions and managed actions.Automatic actions may include downloads of the endpoint computersecurity facility 152 to components of the enterprise facility 102,downloads of updates to existing endpoint computer security facilitiesof the enterprise facility 102, uploaded network interaction requestsfrom enterprise facility 102 components to the threat managementfacility 100, and the like. In embodiments, automatic interactionsbetween the enterprise facility 102 and the threat management facility100 may be configured by the threat management facility 100 and anadministration facility 134 in the enterprise facility 102. Theadministration facility 134 may configure policy rules that determineinteractions, such as developing rules for accessing applications, as inwho is authorized and when applications may be used; establishing rulesfor ethical behavior and activities; rules governing the use ofentertainment software such as games, or personal use software such asIM and VoIP; rules for determining access to enterprise facility 102computing resources, including authentication, levels of access, riskassessment, and usage history tracking; rules for when an action is notallowed, such as whether an action is completely deigned or justmodified in its execution; and the like. The administration facility 134may also establish license management, which in turn may furtherdetermine interactions associated with a licensed application. Inembodiments, interactions between the threat management facility 100 andthe enterprise facility 102 may provide threat protection to theenterprise facility 102 by managing the flow of network data into andout of the enterprise facility 102 through automatic actions that may beconfigured by the threat management facility 100 or the administrationfacility 134.

Client facilities within the enterprise facility 102 may be connected tothe enterprise facility 102 network by way of wired network facilities148A or wireless network facilities 148B. Client facilities connected tothe enterprise facility 102 network via a wired facility 148A orwireless facility 148B may receive similar protection, as bothconnection types are ultimately connected to the same enterprisefacility 102 network, with the same endpoint computer security facility152, and the same threat protected enterprise facility 102 environment.Mobile wireless facility clients 144B-F, because of their ability toconnect to any wireless 148B,D network access point, may connect to theInternet 154 outside the enterprise facility 102, and therefore outsidethe threat-protected environment of the enterprise facility 102. In thisinstance the mobile client facility (e.g., the clients 144 B-F), if notfor the presence of the endpoint computer security facility 152 mayexperience a malware attack or perform actions counter to enterprisefacility 102 established policies. In addition, there may be a pluralityof ways for the threat management facility 100 to protect theout-of-enterprise facility 102 mobile client facility (e.g., the clients144 D-F) that has an embedded endpoint computer security facility 152,such as by providing URI filtering in personal routers, using a webappliance as a DNS proxy, or the like. Mobile client facilities that arecomponents of the enterprise facility 102 but temporarily outsideconnectivity with the enterprise facility 102 network may be providedwith the same threat protection and policy control as client facilitiesinside the enterprise facility 102. In addition, mobile the clientfacilities may receive the same interactions to and from the threatmanagement facility 100 as client facilities inside the enterprisefacility 102, where the mobile client facilities may be considered avirtual extension of the enterprise facility 102, receiving all the sameservices via their embedded endpoint computer security facility 152.

Interactions between the threat management facility 100 and thecomponents of the enterprise facility 102, including mobile clientfacility extensions of the enterprise facility 102, may ultimately beconnected through the Internet 154. Threat management facility 100downloads and upgrades to the enterprise facility 102 may be passed fromthe firewalled networks of the threat management facility 100 through tothe endpoint computer security facility 152 equipped components of theenterprise facility 102. In turn the endpoint computer security facility152 components of the enterprise facility 102 may upload policy andaccess requests back across the Internet 154 and through to the threatmanagement facility 100. The Internet 154 however, is also the paththrough which threats may be transmitted from their source. Thesenetwork threats 104 may include threats from a plurality of sources,including without limitation, websites, e-mail, IM, VoIP, applicationsoftware, and the like. These threats may attempt to attack a mobileenterprise client facility (e.g., the clients 144B-F) equipped with anendpoint computer security facility 152, but in embodiments, as long asthe mobile client facility is embedded with an endpoint computersecurity facility 152, as described above, threats may have no bettersuccess than if the mobile client facility were inside the enterprisefacility 102.

However, if the mobile client facility were to attempt to connect intoan unprotected connection point, such as at a secondary location 108that is not a part of the enterprise facility 102, the mobile clientfacility may be required to request network interactions through thethreat management facility 100, where contacting the threat managementfacility 100 may be performed prior to any other network action. Inembodiments, the client facility's 144 endpoint computer securityfacility 152 may manage actions in unprotected network environments suchas when the client facility (e.g., client 144F) is in a secondarylocation 108 or connecting wirelessly to a non-enterprise facility 102wireless Internet connection, where the endpoint computer securityfacility 152 may dictate what actions are allowed, blocked, modified, orthe like. For instance, if the client facility's 144 endpoint computersecurity facility 152 is unable to establish a secured connection to thethreat management facility 100, the endpoint computer security facility152 may inform the user of such, and recommend that the connection notbe made. In the instance when the user chooses to connect despite therecommendation, the endpoint computer security facility 152 may performspecific actions during or after the unprotected connection is made,including running scans during the connection period, running scansafter the connection is terminated, storing interactions for subsequentthreat and policy evaluation, contacting the threat management facility100 upon first instance of a secured connection for further actions andor scanning, restricting access to network and local resources, or thelike. In embodiments, the endpoint computer security facility 152 mayperform specific actions to remediate possible threat incursions orpolicy violations during or after the unprotected connection.

The secondary location 108 may have no endpoint computer securityfacilities 152 as a part of its computer components, such as itsfirewalls 138B, servers 142B, clients 144G, hubs and routers 148C-D, andthe like. As a result, the computer components of the secondary location108 may be open to threat attacks, and become potential sources ofthreats, as well as any mobile enterprise facility clients 144B-F thatmay be connected to the secondary location's 108 network. In thisinstance, these computer components may now unknowingly spread a threatto other components connected to the network.

Some threats may not come directly from the Internet 154, such as fromnon-enterprise facility controlled mobile devices that are physicallybrought into the enterprise facility 102 and connected to the enterprisefacility 102 client facilities. The connection may be made from directconnection with the enterprise facility's 102 client facility, such asthrough a USB port, or in physical proximity with the enterprisefacility's 102 client facility such that a wireless facility connectioncan be established, such as through a Bluetooth connection. Thesephysical proximity threats 110 may be another mobile computing device, aportable memory storage device, a mobile communications device, or thelike, such as CDs and DVDs, memory sticks, flash drives, external harddrives, cell phones, PDAs, MP3 players, digital cameras, point-to-pointdevices, digital picture frames, digital pens, navigation devices,tablets, appliances, and the like. A physical proximity threat 110 mayhave been previously infiltrated by network threats while connected toan unprotected network connection outside the enterprise facility 102,and when connected to the enterprise facility 102 client facility, posea threat. Because of their mobile nature, physical proximity threats 110may infiltrate computing resources in any location, such as beingphysically brought into the enterprise facility 102 site, connected toan enterprise facility 102 client facility while that client facility ismobile, plugged into an unprotected client facility at a secondarylocation 108, and the like. A mobile device, once connected to anunprotected computer resource, may become a physical proximity threat110. In embodiments, the endpoint computer security facility 152 mayprovide enterprise facility 102 computing resources with threatprotection against physical proximity threats 110, for instance, throughscanning the device prior to allowing data transfers, through securityvalidation certificates, through establishing a safe zone within theenterprise facility 102 computing resource to transfer data into forevaluation, and the like.

Having provided an overall context for threat detection, the descriptionnow turns to a brief discussion of an example of a computer system thatmay be used for any of the entities and facilities described above.

FIG. 2 illustrates a computer system. In general, the computer system200 may include a computing device 210 connected to a network 202, e.g.,through an external device 204. The computing device 210 may be orinclude any type of network endpoint or endpoints as described herein,e.g., with reference to FIG. 1 above. For example, the computing device210 may include a desktop computer workstation. The computing device 210may also or instead be any suitable device that has processes andcommunicates over a network 202, including without limitation a laptopcomputer, a desktop computer, a personal digital assistant, a tablet, amobile phone, a television, a set top box, a wearable computer (e.g.,watch, jewelry, or clothing), a home device (e.g., a thermostat or ahome appliance controller), just as some examples. The computing device210 may also or instead include a server, or it may be disposed on aserver.

The computing device 210 may be used for any of the entities describedin the threat management environment described above with reference toFIG. 1 . For example, the computing device 210 may be a server, a clientan enterprise facility, a threat management facility, or any of theother facilities or computing devices described therein. In certainaspects, the computing device 210 may be implemented using hardware(e.g., a desktop computer), software (e.g., in a virtual machine or thelike), or a combination of software and hardware (e.g., with programsexecuting on the desktop computer), and the computing device 210 may bea standalone device, a device integrated into another entity or device,a platform distributed across multiple entities, or a virtualized deviceexecuting in a virtualization environment.

The network 202 may include any network described above, e.g., datanetwork(s) or internetwork(s) suitable for communicating data andcontrol information among participants in the computer system 200. Thismay include public networks such as the Internet, private networks, andtelecommunications networks such as the Public Switched TelephoneNetwork or cellular networks using third generation cellular technology(e.g., 3G or IMT-2000), fourth generation cellular technology (e.g., 4G,LTE. MT-Advanced, E-UTRA, etc.) or WiMax-Advanced (IEEE 802.16m)) and/orother technologies, as well as any of a variety of corporate area,metropolitan area, campus or other local area networks or enterprisenetworks, along with any switches, routers, hubs, gateways, and the likethat might be used to carry data among participants in the computersystem 200. The network 202 may also include a combination of datanetworks, and need not be limited to a strictly public or privatenetwork.

The external device 204 may be any computer or other remote resourcethat connects to the computing device 210 through the network 202. Thismay include threat management resources such as any of thosecontemplated above, gateways or other network devices, remote servers orthe like containing content requested by the computing device 210, anetwork storage device or resource, a device hosting malicious content,or any other resource or device that might connect to the computingdevice 210 through the network 202.

The computing device 210 may include a processor 212, a memory 214, anetwork interface 216, a data store 218, and one or more input/outputdevices 220. The computing device 210 may further include or be incommunication with peripherals 222 and other external input/outputdevices 224.

The processor 212 may be any as described herein, and in general becapable of processing instructions for execution within the computingdevice 210 or computer system 200. The processor 212 may include asingle-threaded processor or a multi-threaded processor. The processor212 may be capable of processing instructions stored in the memory 214or on the data store 218.

The memory 214 may store information within the computing device 210 orcomputer system 200. The memory 214 may include any volatile ornon-volatile memory or other computer-readable medium, including withoutlimitation a Random Access Memory (RAM), a flash memory, a Read OnlyMemory (ROM), a Programmable Read-only Memory (PROM), an Erasable PROM(EPROM), registers, and so forth. The memory 214 may store programinstructions, program data, executables, and other software and datauseful for controlling operation of the computing device 200 andconfiguring the computing device 200 to perform functions for a user.The memory 214 may include a number of different stages and types fordifferent aspects of operation of the computing device 210. For example,a processor may include on-board memory and/or cache for faster accessto certain data or instructions, and a separate, main memory or the likemay be included to expand memory capacity as desired.

The memory 214 may, in general, include a non-volatile computer readablemedium containing computer code that, when executed by the computingdevice 200 creates an execution environment for a computer program inquestion, e.g., code that constitutes processor firmware, a protocolstack, a database management system, an operating system, or acombination of the foregoing, and/or code that performs some or all ofthe steps set forth in the various flow charts and other algorithmicdescriptions set forth herein. While a single memory 214 is depicted, itwill be understood that any number of memories may be usefullyincorporated into the computing device 210. For example, a first memorymay provide non-volatile storage such as a disk drive for permanent orlong-term storage of files and code even when the computing device 210is powered down. A second memory such as a random access memory mayprovide volatile (but higher speed) memory for storing instructions anddata for executing processes. A third memory may be used to improveperformance by providing even higher speed memory physically adjacent tothe processor 212 for registers, caching and so forth.

The network interface 216 may include any hardware and/or software forconnecting the computing device 210 in a communicating relationship withother resources through the network 202. This may include remoteresources accessible through the Internet, as well as local resourcesavailable using short range communications protocols using, e.g.,physical connections (e.g., Ethernet), radio frequency communications(e.g., WiFi), optical communications, (e.g., fiber optics, infrared, orthe like), ultrasonic communications, or any combination of these orother media that might be used to carry data between the computingdevice 210 and other devices. The network interface 216 may, forexample, include a router, a modem, a network card, an infraredtransceiver, a radio frequency (RF) transceiver, a near fieldcommunications interface, a radio-frequency identification (RFID) tagreader, or any other data reading or writing resource or the like.

More generally, the network interface 216 may include any combination ofhardware and software suitable for coupling the components of thecomputing device 210 to other computing or communications resources. Byway of example and not limitation, this may include electronics for awired or wireless Ethernet connection operating according to the IEEE802.11 standard (or any variation thereof), or any other short or longrange wireless networking components or the like. This may includehardware for short range data communications such as Bluetooth or aninfrared transceiver, which may be used to couple to other localdevices, or to connect to a local area network or the like that is inturn coupled to a data network 202 such as the Internet. This may alsoor instead include hardware/software for a WiMax connection or acellular network connection (using, e.g., CDMA, GSM, LTE, or any othersuitable protocol or combination of protocols). The network interface216 may be included as part of the input/output devices 220 orvice-versa.

The data store 218 may be any internal memory store providing acomputer-readable medium such as a disk drive, an optical drive, amagnetic drive, a flash drive, or other device capable of providing massstorage for the computing device 210. The data store 218 may storecomputer readable instructions, data structures, program modules, andother data for the computing device 210 or computer system 200 in anon-volatile form for subsequent retrieval and use. For example, thedata store 218 may store without limitation one or more of the operatingsystem, application programs, program data, databases, files, and otherprogram modules or other software objects and the like.

The input/output interface 220 may support input from and output toother devices that might couple to the computing device 210. This may,for example, include serial ports (e.g., RS-232 ports), universal serialbus (USB) ports, optical ports, Ethernet ports, telephone ports, audiojacks, component audio/video inputs, HDMI ports, and so forth, any ofwhich might be used to form wired connections to other local devices.This may also or instead include an infrared interface, RF interface,magnetic card reader, or other input/output system for coupling in acommunicating relationship with other local devices. It will beunderstood that, while the network interface 216 for networkcommunications is described separately from the input/output interface220 for local device communications, these two interfaces may be thesame, or may share functionality, such as where a USB port is used toattach to a WiFi accessory, or where an Ethernet connection is used tocouple to a local network attached storage.

A peripheral 222 may include any device used to provide information toor receive information from the computing device 200. This may includehuman input/output (I/O) devices such as a keyboard, a mouse, a mousepad, a track ball, a joystick, a microphone, a foot pedal, a camera, atouch screen, a scanner, or other device that might be employed by theuser 230 to provide input to the computing device 210. This may also orinstead include a display, a speaker, a printer, a projector, a headsetor any other audiovisual device for presenting information to a user.The peripheral 222 may also or instead include a digital signalprocessing device, an actuator, or other device to support control orcommunication to other devices or components. Other I/O devices suitablefor use as a peripheral 222 include haptic devices, three-dimensionalrendering systems, augmented-reality displays, magnetic card readers,and so forth. In one aspect, the peripheral 222 may serve as the networkinterface 216, such as with a USB device configured to providecommunications via short range (e.g., BlueTooth, WiFi, Infrared, RF, orthe like) or long range (e.g., cellular data or WiMax) communicationsprotocols. In another aspect, the peripheral 222 may provide a device toaugment operation of the computing device 210, such as a globalpositioning system (GPS) device, a security dongle, or the like. Inanother aspect, the peripheral may be a storage device such as a flashcard, USB drive, or other solid state device, or an optical drive, amagnetic drive, a disk drive, or other device or combination of devicessuitable for bulk storage. More generally, any device or combination ofdevices suitable for use with the computing device 200 may be used as aperipheral 222 as contemplated herein.

Other hardware 226 may be incorporated into the computing device 200such as a co-processor, a digital signal processing system, a mathco-processor, a graphics engine, a video driver, and so forth. The otherhardware 226 may also or instead include expanded input/output ports,extra memory, additional drives (e.g., a DVD drive or other accessory),and so forth.

A bus 232 or combination of busses may serve as an electromechanicalplatform for interconnecting components of the computing device 200 suchas the processor 212, memory 214, network interface 216, other hardware226, data store 218, and input/output interface. As shown in the figure,each of the components of the computing device 210 may be interconnectedusing a system bus 232 or other communication mechanism forcommunicating information.

Methods and systems described herein can be realized using the processor212 of the computer system 200 to execute one or more sequences ofinstructions contained in the memory 214 to perform predetermined tasks.In embodiments, the computing device 200 may be deployed as a number ofparallel processors synchronized to execute code together for improvedperformance, or the computing device 200 may be realized in avirtualized environment where software on a hypervisor or othervirtualization management facility emulates components of the computingdevice 200 as appropriate to reproduce some or all of the functions of ahardware instantiation of the computing device 200.

FIG. 3 illustrates a threat management system as contemplated herein. Ingeneral, the system may include an endpoint 302, a firewall 304, aserver 306 and a threat management facility 308 coupled to one anotherdirectly or indirectly through a data network 305, all as generallydescribed above. Each of the entities depicted in FIG. 3 may, forexample, be implemented on one or more computing devices such as thecomputing device described above with reference to FIG. 2 . A number ofsystems may be distributed across these various components to supportthreat detection, such as a coloring system 310, a key management system312 and a heartbeat system 314, each of which may include softwarecomponents executing on any of the foregoing system components, and eachof which may communicate with the threat management facility 308 and anendpoint threat detection agent 320 executing on the endpoint 302 tosupport improved threat detection and remediation.

The coloring system 310 may be used to label or ‘color’ software objectsfor improved tracking and detection of potentially harmful activity. Thecoloring system 310 may, for example, label files, executables,processes, network communications, data sources and so forth with anysuitable. A variety of techniques may be used to select static and/ordynamic labels for any of these various software objects, and to managethe mechanics of applying and propagating coloring information asappropriate. For example, a process may inherit a color from anapplication that launches the process. Similarly a file may inherit acolor from a process when it is created or opened by a process, and/or aprocess may inherit a color from a file that the process has opened.More generally, any type of labeling, as well as rules for propagating,inheriting, changing, or otherwise manipulating such labels, may be usedby the coloring system 310 as contemplated herein. A suitable coloringsystem is described in greater detail below with reference to FIG. 4 .

The key management system 312 may support management of keys for theendpoint 302 in order to selectively permit or prevent access to contenton the endpoint 302 on a file-specific basis, a process-specific basis,an application-specific basis, a user-specific basis, or any othersuitable basis in order to prevent data leakage, and in order to supportmore fine-grained and immediate control over access to content on theendpoint 302 when a security compromise is detected. Thus for example,if a particular process executing on the endpoint is compromised, orpotentially compromised or otherwise under suspicion, keys to thatprocess may be revoked in order to prevent, e.g., data leakage or othermalicious activity. A suitable key management system useful in thiscontext is described in greater detail below with reference to FIG. 5 .

The heartbeat system 314 may be used to provide periodic or aperiodicinformation from the endpoint 302 or other system components aboutsystem health, security, status, and so forth. A heartbeat may beencrypted or plaintext, or some combination of these, and may becommunicated unidirectionally (e.g., from the endpoint 308 to the threatmanagement facility 308) or bidirectionally (e.g., between the endpoint302 and the server 306, or any other pair of system components) on anyuseful schedule. A suitable heartbeat system is described in greaterdetail below with reference to FIG. 6 .

In general, these various monitoring and management systems maycooperate to provide improved threat detection and response. Forexample, the coloring system 310 may be used to evaluate when aparticular process is potentially opening inappropriate files, and apotential threat may be confirmed based on an interrupted heartbeat fromthe heartbeat system 314. The key management system 312 may then bedeployed to revoke keys to the process so that no further files can beopened, deleted or otherwise modified. More generally, the cooperationof these systems enables a wide variety of reactive measures that canimprove detection and remediation of potential threats to an endpoint.

FIG. 4 illustrates a system for behavioral tracking, coloring, andgeneration of indications of compromise (IOCs). In general, the system400 may include a number of entities participating in a threatmanagement process such as any of the entities and threat managementprocesses described herein. The threat management process may forexample employ techniques such as behavioral tracking, encryption,endpoint recording, reputation-based threat detection, behavioral-basedthreat detection, signature-based threat detection, and combinations ofthe foregoing, or any other suitable techniques for detecting threats toendpoints in a network.

In general, the system 400 may include a number of endpoints 402, 412and a threat management facility 404 in an enterprise 410, such as anyof the enterprises described above. An external analysis facility 406may analyze threat data and provide rules and the like for use by thethreat management facility 404 and endpoints 402, 412 in managingthreats to the enterprise 410. The threat management facility 404 mayreside in a local appliance (e.g., embedded within, or locally coupledto the endpoint 402), a virtual appliance (e.g., which could be run by aprotected set of systems on their own network system(s)), a privatecloud, a public cloud, and so forth. The analysis facility 406 may storelocally-derived threat information. The analysis facility 406 may alsoor instead receive threat information from a third party source 416 suchas MITRE Corporation or any other public, private, educational or otherorganization that gathers information on network threats and providesanalysis and threat detection information for use by others. Each ofthese components may be configured with suitable programming toparticipate in the various threat detection and management techniquescontemplated herein. The threat management facility 404 may monitor anystream of data from an endpoint 402 exclusively, or use the full contextof intelligence from the stream of all protected endpoints 402, 412 orsome combination of these.

The endpoint 402 may be any of the endpoints described herein, or anyother device or network asset that might join or participate in theenterprise 410 or otherwise operate on an enterprise network. This may,for example, include a server, a client such as a desktop computer or amobile computing device (e.g., a laptop computer, a wearable device, atablet, and the like), a cellular phone, a smart phone, or othercomputing device suitable for participating in the enterprise 410.

In general, the endpoint 402 may include any number of computing objectssuch as an object 418 labeled with a descriptor 420. While the termobject has a number of specific meanings in the art, and in particularin object-oriented programming, it will be understood that the term‘object’ as used herein is intended to be significantly broader, and mayinclude any data, process, file or combination of these includingwithout limitation any process, application, executable, script, dynamiclinked library, file, data, database, data source, data structure,function, resource locator (e.g., uniform resource locator (URL) orother uniform resource identifier (URI)), or the like that might bemanipulated by one of the computing devices described herein.

An object 418 may also or instead include a remote resource, such as aresource identified in a URL. That is, while the objects 418 in FIG. 4are depicted as residing on the endpoint 402, an object 418 may alsoreside elsewhere in the system 400, while still being labeled with adescriptor 420 and tracked by the monitor 421 of the endpoint 402. Theobject 418 may be an item that is performing an action or causing anevent, or the object 418 may be an item that is receiving the action orresult of an event (i.e., the item in the system 400 being acted upon).

Where the object 418 is data or includes data, the object 418 may beencrypted or otherwise protected, or the object 418 may be unencryptedor otherwise unprotected. The object 418 may be a process or othercomputing object that performs an action, which may include a singleevent or a collection or sequence of events taken by a process. Theobject 418 may also or instead include an item such as a file or linesof code that are executable to perform such actions. The object 418 mayalso or instead include a computing component upon which an action istaken, e.g., a system setting (e.g., a registry key or the like), a datafile, a URL, or the like. The object 418 may exhibit a behavior such asan interaction with another object or component of the system 400.

In one aspect, objects 418 may be described in terms of persistence. Theobject 418 may, for example, be a part of a process, and remainpersistent as long as that process is alive. The object 418 may insteadbe persistent across an endpoint 402 and remain persistent as long as anendpoint 402 is active or alive. The object 418 may instead be a globalobject having persistence outside of an endpoint 418, such as a URL or adata store. In other words, the object 418 may be a persistent objectwith persistence outside of the endpoint.

Although many if not most objects 418 will typically be benign objectsthat may be found on a normal, operating endpoint, an object 418 maycontain software associated with an advanced persistent threat (APT) orother malware that resides partially or entirely on the endpoint 402.The associated software may have reached the endpoint 402 in a varietyof ways, and may have been placed manually or automatically on theendpoint 402 by a malicious source. It will be understood that theassociated software may take any number of forms and have any number ofcomponents. For example, the associated software may include anexecutable file that can execute independently, or the associatedsoftware may be a macro, plug-in, or the like that executes withinanother application. Similarly, the associated software may manifest asone or more processes or threads executing on the endpoint 402. Further,the associated software may install from a file on the endpoint 402 (ora file remote from the endpoint 402), and the associated software maycreate one or more files such as data files or the like while executing.Associated software should be understood to generally include all suchfiles and processes except where a specific file or process is morespecifically noted.

A threat such as an APT may also take the form of an attack where noaltered or additional software is directly added or modified on theendpoint 402. Instead, an adversary may reuse existing software on thesystem 400 to perform the attacks. It is for this reason that simplyscanning for associated software may be insufficient for the detectionof APTs and it may be preferable to detect APTs based on the behavior ofthe software and associated objects 418 that are used by, for, and withthat software.

An object coloring system 414 may apply descriptors 420 to objects 418on the endpoint 402. This may be performed continuously by a backgroundprocess on the endpoint 402, or it may occur whenever an object 418 isinvolved in an action, such as when a process makes a call to anapplication programming interface (API) or takes some other action, orwhen a URL is used to initiate a network request, or when a read or awrite is performed on data in a file. This may also or instead include acombination of these approaches as well as other approaches, such as bylabeling a file or application when it is moved to the endpoint 402, orwhen the endpoint 402 is started up or instantiated. In general, theobject coloring system 414 may add, remove or change a color at anylocation and at any moment that can be practicably instrumented on acomputer system.

As noted above, the term ‘object’ as used herein is intended to includea wide range of computing objects and as such, the manner in whichparticular objects 418 are labeled or ‘colored’ with descriptors 420 mayvary significantly. Any object 418 that is performing an action may becolored at the time of and/or with a label corresponding to the action,or likewise any object 418 that is the target of the action may becolored at the time that it is used and/or with a label corresponding toa process or the like using the object 418. Furthermore, the operatingsystem runtime representation of the object 418 may be colored, or thepersistent object outside of the operating system may be colored (as isthe case for a File Handle or File Object within the operating system orthe actual file as stored in a file system), such as within anencryption header or other header applied to the file, or as part of adirectory attribute or any other persistent location within the file orfile system. A former coloring may be ephemerally tracked while theoperating system maintains the representation and the latter may persistlong after any reboots of the same operating system and likewise havemeaning when read or used by other endpoints 402. For processes, eachfile handle may be supplemented with a pointer or other mechanism forlocating a descriptor 420 for a particular object 420 that is a process.More specifically, each object 418 may be colored in any manner suitablefor appending information to that object 418 so that the correspondingdescriptor 420 can be retrieved and, where appropriate, updated.

The coloring system 414 may apply any suitable rules for adding andchanging descriptors 420 for objects 418. For example, when a processwith a certain descriptor accesses data with a different descriptor, thedescriptor for the process may be updated to correspond to the data, orthe descriptor for the data may be updated to correspond to the process,or some combination of these. Any action by or upon an object 418 maytrigger a coloring rule so that descriptors 420 can be revised at anyrelevant time(s) during processing.

In one aspect, colors will not explicitly indicate a compromisedsecurity state or other good/bad types of distinctions (although theymay be adapted to this use). Instead, colors may record some knowninformation or understanding about an object 418, such as a source, apurpose, and so forth. In this context, colors will not be used to labelactual or potential security compromises, but to identifyinconsistencies among interacting objects 418, and to restrict orcontrol access and use accordingly. For example, where an endpoint usesfile-system-based encryption as described herein, a process that iscolored as exposed to external resources (e.g., the Internet) may beprohibited from accessing cleartext data for protected files. Colors canalso be used in other contexts such as intrusion prevention, routingrules, and detection of odd or questionable behavior.

In one aspect, colors may be implemented as flags associated withobjects 418 that provide a short hand cache of potentially relevantinformation. While this information could also be obtained for an object418 through a careful inspection of related activity logs or other datarecording activities, the use of a cache of flags for coloringinformation makes the coloring information directly available andimmediately actionable, as distinguished from post hoc forensicactivities that are otherwise supported by data logging.

In one aspect, colors as contemplated herein may fall into two differentcategories: static colors and dynamic colors. Static colors may beexplicitly applied based on, e.g., a controlling application. Forexample, a static color may specify a status of an application or data,or an associated type of application (e.g., productivity, mail client,messaging, browser, word processing, financial, spreadsheet, etc.). Inthis context, a process will generally inherit static colors from asource executable, and will permit inferences for appropriate behaviorand related processes. Dynamic colors may be assigned based on directobservation of executing processes, and may not be inherited ortransferred among processes (although the presence of a dynamic colormay be used to draw another coloring inference upon interaction withanother process). Thus, the inheritance of colors may depend in partupon the type of color that is applied, or upon explicit inheritancerules provided for a particular color.

A descriptor 420 may take a variety of forms, and may in general includeany information selected for relevance to threat detection. This may,for example, be a simple categorization of data or processes such astrusted or untrusted. For example, in one embodiment described herein,data and processes are labeled as either ‘IN’ (e.g., trusted) or ‘OUT’(e.g., untrusted). The specific content of the label is unimportant, andthis may be a binary flag, text string, encrypted data or otherhuman-readable and/or machine-readable identifier, provided that thedescriptor 420 can facilitate discrimination among labeled files—in thisexample, between trusted objects 418 and untrusted objects 418 so that,e.g., trusted data can be selectively decrypted or encrypted for usewith trusted processes. Similarly, data may be labeled as corporate dataor private data, with similar type-dependent processing provided. Forexample, private data may be encrypted with a key exclusively controlledby the data owner, while corporate data may be encrypted using aremotely managed key ring for an enterprise operated by the corporation.

In another aspect, the descriptor 420 may provide a multi-tiered orhierarchical description of the object 418 including any informationuseful for characterizing the object 418 in a threat management context.For example, in one useful configuration the descriptor 420 may includea type or category, static threat detection attributes, and an explicitidentification. The type or category for the object 418 may be anycategory or the like that characterizes a general nature or use of theobject 418 as inferred from behavior and other characteristics. Thismay, for example, include categories such as ‘game,’ ‘financial,’‘application,’ ‘electronic mail,’ ‘image,’ ‘video,’ ‘browser,’‘antivirus,’ and so forth. The category may be more granular, or mayinclude hierarchical categories such as ‘application:spreadsheet,’‘application:wordprocessing,’ and so forth. Such colors may be directlyinferred from a single action, a sequence of actions, or a combinationof actions and other colors, including, e.g., colors of processes andfiles related to a particular action, or other objects 418 that providecontext for a particular action or group of actions. One or more colorsmay also or instead be explicitly provided by a user or a process, orotherwise automatically or manually attributed to computer objects ascontemplated herein.

The static threat detection attributes may be any readily ascertainablecharacteristics of the object 418 useful in threat detection. This may,for example, include an antivirus signature, a hash, a file size, fileprivileges, a process user, a path or director, and so forth. Staticthreat detection attributes may also include attributes that are derivedby or supplied from other sources. For example, static threat detectionattributes may include a reputation for an object 418, which may beexpressed in any suitable or useful level of granularity such as withdiscrete categories (trusted/untrusted/unknown) or with a numericalscore or other quantitative indicator. The explicit identification may,in general, be what an object 418 calls itself, e.g., a file name orprocess name.

Some actions may transfer colors from the subject of the action to thetarget of the action. For example, when a process creates sub-processes,the sub-processes may inherit the colors of its parent(s). By way ofanother example, when a process is initially loaded from an executable,it may inherit the color(s) stored in the file system for or with theexecutable.

In general, the descriptor 420 may be provided in any suitable format.The descriptor 420 may for example be formed as a vector of binary flagsor other attributes that form the ‘color’ or description of an object418. The descriptor 420 may also, where appropriate, include scalarquantities for certain properties. For example, it may be relevant howmany times a system file was accessed, how many file handles a processhas open, how many times a remote resource was requested or how long aremote resource is connected, and this information may be suitablyencoded in the descriptor 420 for use in coloring objects with thecoloring system 414 and applying rules for IOC detection by the IOCmonitor 421.

An indication of compromise (IOC) monitor 421 may be provided toinstrument the endpoint 402 so that any observable actions by orinvolving various objects 418 can be detected. As with the coloringsystem 414, it will be understood that the types of observable actionswill vary significantly, and the manner in which the endpoint 402 isinstrumented to detect such actions will depend on the particular typeof object 418. For example, for files or the like, an API for a filesystem may be used to detect reads, writes, and other access (e.g.,open, read, write, move, copy, delete, etc.), and may be configured toreport to or otherwise initiate monitoring of the action taken with thefile through the file system. As another example, kernel objects may beinstrumented at the corresponding object handle or in some other manner.As a further example, a kernel driver may be used for intercepting aprocess startup. While a wide variety of objects are contemplatedherein, one of ordinary skill in the art may create suitableinstrumentation for any computing object so that it may be monitored bythe IOC monitor 421.

It will be noted that suitable instrumentation may be created for avariety of functions and circumstances. For example, instrumentation mayusefully track requests for network access or other actions back to aparticular application or process, or data payloads back to a particularfile or data location. One of ordinary skill in the art can readilyimplement suitable traces and/or logging for any such information thatmight be useful in a particular IOC monitoring operation.

In general, the IOC monitor 421 applies rules to determine when there isan IOC 422 suitable for reporting to a threat management facility 404.It will be understood that an endpoint 402 may, in suitablecircumstances and with appropriate information, take immediate localaction to remediate a threat. However, the monitor 421 mayadvantageously accumulate a sequence of actions, and still moreadvantageously may identify inconsistencies or unexpected behaviorwithin a group of actions with improved sensitivity by comparingdescriptors 420 for various objects 418 involved in relevant actions andevents. In this manner, rules may be applied based upon the descriptors420 that better discriminate malicious activity while reducing thequantity and frequency of information that must be communicated to aremote threat management facility 404. At the same time, all of therelevant information provided by the descriptors 420 can be sent in anIOC 422 when communicating a potential issue to the threat managementfacility 404. For example, during the course of execution, a specificprocess (as evidenced by its observed actions) may be assigned colordescriptors indicating that it is a browser process. Further, thespecific process may be assigned an attribute indicating that it hasexposed itself to external URLs or other external data. Subsequently,the same process may be observed to be taking an action suitable for aninternal or system process, such as opening up shared memory to anotherprocess that has coloring descriptions indicating that it is a systemprocess. When this last action is observed, an inconsistency in thevarious color descriptors between the subject of the action—theexternally exposed browser process—and the target of the action mayresult in a well-defined IOC, which may be directly processed withimmediate local action taken. The IOC may also or instead be reportedexternally as appropriate.

Thus, an endpoint 402 in an enterprise 410 may be instrumented with acoloring system 414 and monitor 421 to better detect potentiallymalicious activity using descriptors 420 that have been selected forrelevance to threat detection along with a corresponding set of rulesdeveloped for the particular descriptors 420 that are being used tolabel or color various objects 418. By way of example, the object 418may be a web browser that starts off being colored as a ‘browser’ and an‘internet facing’ application. Based on this descriptor 420, a range ofbehaviors or actions may be considered normal, such as accessing remotenetwork resources. However, if an object 418 colored with thisdescriptor 420 attempted to elevate privileges for a process, or toaccess a registry or system files, then this inconsistency in action maytrigger a rule violation and result in an IOC 422.

In general, any action or series of actions that cumulatively invoke aparticular reporting or action rule may be combined into an IOC 422 andcommunicated to the threat management facility 404. For example, an IOC422 may include a malicious or strange behavior, or an indication of amalicious or strange behavior. The IOC 422 may be a normalized IOC thatexpresses one or more actions in a platform independent manner. That is,the IOC 422 may express a malicious behavior or suspected maliciousbehavior without reference to platform-specific information such asdetails of an operating system (e.g., iOS, MacOS, Windows, Android,Linux, and so forth), hardware, applications, naming conventions, and soforth. Thus, a normalized IOC may be suitable for identifying aparticular threat across multiple platforms, and may include platformindependent processes, actions, or behaviors, or may express suchprocess, actions, or behaviors in a platform independent manner. Thenormalized IOC may be generated from the IOC 422, e.g., it may be aconverted version of the IOC 422 suitable for use with multipleplatforms, or it may simply be any IOC 422 that has been created in aplatform independent form. Process colorization (i.e., using thecoloring system 414) as described herein may be used to create anormalized IOC.

In general, a threat management facility 404 for the enterprise 410 mayinclude an IOC collector 426 that receives the IOC 422 from the endpoint402 and determines an appropriate action. This may include any suitableremedial action, or where one or more IOCs 422 are inconclusive,continued monitoring or increased monitoring as appropriate.

The threat management facility 404 may provide a variety of threatmanagement or monitoring tools 424, any of which may be deployed inresponse to IOCs 422 collected by the IOC collector 426. These tools 424may include without limitation a scanning engine,whitelisting/blacklisting, reputation analysis, web filtering, anemulator, protection architecture, live protection, runtime detection,APT detection, network antivirus products, IOC detection, access logs, aheartbeat, a sandbox or quarantine system, and so forth.

The analysis facility 406 may provide a remote processing resource foranalyzing malicious activities and creating rules 434 suitable fordetecting IOCs 422 based on objects 420 and descriptors 420. It isgenerally contemplated that suitable attributes of certain descriptors418 and one or more rules 434 may be developed together so that objects418 can be appropriately labeled with descriptors 420 that permitinvocation of rules 434 and creation of IOCs 422 at appropriate times.The analysis facility 406 may include a variety of analysis tools 428including, without limitation, tools for regular expression,whitelisting/blacklisting, crowd sourcing, identifiers, and so forth.The analysis tools 428 may also or instead include information and toolssuch as URL look-ups, genotypes, identities, file look-up, reputations,and so forth. The analysis facility 406 may also provide numerousrelated functions such as an interface for receiving information on new,unknown files or processes, and for testing of such code or content in asandbox on the analysis facility 406.

The analysis facility 406 may also or instead include a compromisedetector 430, where the compromise detector 430 is configured to receivenew threat information for analysis and creation of new rules anddescriptors as appropriate, as well as corresponding remedial actions.The compromise detector 430 may include any tools described herein orotherwise known in the art for detecting compromises or evaluating newthreats in an enterprise 410.

In general, a rule 434 may be manually created with correspondinghuman-readable semantics, e.g., where a process is labeled as a browserprocess or other category or type that can be interpreted by a human. Itshould, however, be appreciated that the compromise detector 430 mayalso be configured to automatically generate descriptors 420 and rules434 suitable for distribution to a threat management facility 404 and anendpoint 402. In this latter mode, the meaning of a particulardescriptor 420 may not have a readily expressible human-readablemeaning. Thus, it will be understood that attributes selected forrelevance to threat detection may include conventional attributes, aswell as attributes without conventional labels or meaning except in thecontext of a particular, computer-generated rule for threat detection.

In general, the analysis facility 406 may be within an enterprise 410,or the analysis facility 406 may be external to the enterprise 410 andadministered, for example, by a trusted third party. Further, athird-party source 416 may provide additional threat data 438 oranalyses for use by the analysis facility 406 and the threat managementfacility 404. The third-party resource 416 may be a data resource thatprovides threat data 438 and analyses, where the threat data 438 is anydata that is useful in detecting, monitoring, or analyzing threats. Forexample, the threat data 438 may include a database of threats,signatures, and the like. By way of example, the third-party resource416 may be a resource provided by The MITRE Corporation.

The system 400 may include a reputation engine 440 storing a pluralityof reputations 442. The reputation engine 440 may include a reputationmanagement system for the generation, analysis, identification, editing,storing, etc., of reputations 442. The reputation engine 440 may includereputation-based filtering, which may be similar to the reputationfiltering discussed above with reference to FIG. 1 . The reputationengine 440 may be located on the threat management facility 404 or theendpoint 402 as shown in FIG. 4 , or the reputation engine 440 may belocated elsewhere in the system 400. The reputation engine 440 mayreceive an IOC 422 or a stream of IOCs 422, and may generate or utilizereputations 442 for the IOCs 422. The reputation engine 440 may also orinstead receive actions, behaviors, events, interactions, and so forth,and may generate or utilize reputations 442 for any of the foregoing.The reputation engine 440 may generate or revise a reputation 442 basedon behaviors, actions, events, interactions, IOCs 422, other reputations442, a history of events, data, rules, state of encryption, colors, andso forth. The reputation engine 440 may utilize a third-party resource,e.g., for the third-party resource's reputation data.

The reputations 442 may include reputations for any of the objects 418as described herein. In general, the reputations 442 may relate to thetrustworthiness of the objects 418 or an attribute thereof (e.g., thesource of the object 418, a behavior of the object 418, another objectinteracting with the object 418, and so forth). The reputations 442 mayinclude lists of known sources of malware or known suspicious objects418. The reputations 442 may also or instead include lists of known safeor trusted resources or objects 418. The reputations 442 may be storedin a reputations database included on the reputation engine 440 orlocated elsewhere in the system 400. The reputations 442 may beexpressed in any suitable or useful level of granularity such as withdiscrete categories (e.g., trusted, untrusted, unknown, malicious, safe,etc.) or with a numerical score or other quantitative indicator. Thereputations 442 may also be scaled.

In general, in the system 400 of FIG. 4 , a malicious activity on theendpoint 402 may be detected by the IOC monitor 421, and a correspondingIOC 422 may be transmitted to the threat management facility 404 forremedial action as appropriate. The threat management facility 404 mayfurther communicate one or more IOCs 422 to the analysis facility 406for additional analyses and/or resolution of inconclusive results. Otherdetails and variations are provided below. While the use of coloring andIOCs as contemplated herein can improve threat detection and remediationin a number of ways, the system 400 can be further improved withgranular control over access to endpoint data using an encryptionsystem. A system for key-based management of processes and files on anendpoint is now discussed in greater detail.

FIG. 5 illustrates a system for encryption management. Generally, thesystem 500 may include endpoints 502, an administration host 504, and athreat management facility 506, which may include policy manager 508 andkey manager 510. The system 500 may provide for the management of users512, policies 514, keys 516 (e.g., disposed on key rings 518), andendpoints 502 (e.g., from the administration host 504). The system 500may utilize various storage and processing resources, which may bedisposed in a cloud or the like.

The endpoints 502 may be any of the endpoints as described herein, e.g.,with reference to the other figures. The endpoints 502 may also orinstead include other end user devices and other devices to be managed.The endpoints 502 may include a web browser for use by the users 512,with supporting cryptographic functions implemented using cryptographiclibraries in the web browser. The endpoints 502 may communicate with theother components of the system 500 using any suitable communicationinterface, which may include Secure Socket Layer (SSL) encryption,Hypertext Transfer Protocol Secure (HTTPS), and so forth for additionalsecurity.

The endpoints 502 may include objects as described herein. For example,the endpoints 502 may include processes 520 and files 522. The processes520 may be labeled (e.g., by a coloring system using descriptors asdescribed above) in such a manner that the process is ‘IN,’ where theprocess 520 is in compliance with policies 514 administered for theendpoint 502 from a remote threat management facility 506, or theprocess is ‘OUT,’ where the process 520 is out of compliance with apolicy (or a number of policies) in the policies 514 for an enterprise.This may provide IN processes 520A and OUT processes 520B as shown inFIG. 5 . The files 522 may be similarly labeled by a coloring systemwith descriptors that identify each file 522 as IN, where the file 522complies with the policies 514 and is accordingly encrypted using, e.g.,a remotely managed key ring 518, or the file is OUT, where the file 522does not conform to the policies 514 and is accordingly not encryptedusing the remotely managed key ring 518. This may provide IN files 522Aand OUT files 522B as shown in FIG. 5 . One skilled in the art willrecognize that other objects of the endpoint 502 or other components ofthe system 500 may be labeled in a similar manner where they are eitherIN or OUT. By coloring objects in this manner and basing key access onthe corresponding color, the “IN” software objects may operate in aprotected environment that objectively appears to be in compliance withthe policies 514. Other files and processes may still be used on theendpoint 502, but they will operate in an “OUT” or unprotectedenvironment that cannot obtain access to any of the “IN” content orfunctionality.

In an implementation, the system 500 may include determining whether anendpoint 502 is IN or OUT or whether a component of the endpoint 502 isIN or OUT, which may be based upon a set of rules (e.g., the rulesoutlined herein) or policies such as the policies 514 described herein.In some aspects, if the entire endpoint 502 is OUT—that is, out ofcompliance with one or more policies 514, the endpoint 502 will not havekey access or access to any protected content. Conversely, if theendpoint 502 is IN, the endpoint 502 may have access to protectedcontent. Thus in one aspect, the notion of IN/OUT may be applied at anendpoint level, and data protection may be a consequence of endpointprotection. Endpoint protection may also or instead be applied at a moregranular level, e.g., by determining whether executables, processes 520,files 522, etc., on the endpoint 502 are IN or OUT, which may be basedupon rules or policies 514 as described herein.

The administration host 504 may include a web browser, which may includea cryptography library 524 and a web user interface (e.g., HTML,JavaScript, etc.). An administrator may utilize the web user interfaceto administer a key management system and perform administrativefunctions such as creating and distributing keys 516, establishingsecurity policies, creating key hierarchies and rules, and so forth. Theendpoint 502 may also include a cryptographic library 524 implementingcryptographic protocols for using key material in the key ring 518 toencrypt and decrypt data as needed.

The threat management facility 506 may include any of the threatmanagement facilities or similar systems described herein. In general,the threat management facility 506 may include a policy manager 508 andkey manager 510. Alternatively, one or more of the policy manager 508and key manager 510 may be located elsewhere on a network.

The policy manager 508 may implement one or more policies 514, andmaintain, distribute, and monitor the policies for devices in anenterprise. The policies 514 may include any policies 514 relating tosecure operation of endpoints 502 in an enterprise. This may, forexample, include hardware configuration policies, software configurationpolicies, communication policies, update policies, or any other policiesrelating to, e.g., the configuration of an endpoint 502, communicationsby an endpoint 502, software executing on an endpoint 502 and so forth.Policies 514 may include usage criteria based on, e.g., signatures,indications of compromise, reputation, user identity, and so forth. Withrespect to the key management system contemplated herein, the policies514 may include a cryptographic protocol design, key servers, userprocedures, and other relevant protocols, or these cryptographicprotocols may be provided elsewhere for use by the policy manager 508.The policies 514 may also include any rules for compliance includingthose mentioned above or any other suitable rules or algorithms that canbe applied to determine whether objects and components are ‘IN’ or ‘OUT’as contemplated herein.

The key manager 510 may be part of the threat management facility 506,or it may be remotely managed elsewhere, e.g., in a remote cloudresource or the like. The key manager 510 may also or instead bedisposed on the administration host 504 and one or more endpoints 502 ina manner independent of the threat management facility 506. In thismanner, all cryptographic operations may be isolated from the threatmanagement facility 506 and instead may be performed by a web browser orthe like executing on the administration host 504 or an endpoint 502.The key manager 510 may manage the keys 516, including managing thegeneration, exchange, storage, use, and replacement of keys 516. The keymanager 510 may include a key ring 518, where the keys 516 are disposedon the key ring 518 using one root key 526. The key manager 510 may alsoor instead include a variety of key management and other secureprocesses, including without limitation, administrator registration,establishing trust to endpoints 502, key distribution to endpoints 502,policy deployment, endpoint status reporting, and local key backup.

The users 512 may have full access to encrypted data. Alternatively, theusers 512 may have limited access to encrypted data, or no access toencrypted data. Access may be limited to users 512 using endpoints 502that are deemed ‘IN’ by the system, as well as to processes 520 that areIN, as further described herein.

The keys 210 may include cryptographic keys in a cryptosystem, i.e.,decryption keys. In one aspect, the keys 210 may be disposed on one keyring 218 using one root key 220. In general, the keys 210 may be createdand managed using, e.g., symmetric key technology, asymmetric keytechnology, or any other key technology or combination of keytechnologies suitable for securing data in an enterprise including, forexample the Data Encryption Standard (DES), Triple DES, AdvancedEncryption Standard (AES), and so forth. The cryptosystem may also orinstead include any suitable public key infrastructure or the likesupporting the distribution and use of keys for encryption, digitalsignatures, and so forth.

The key ring 518 may facilitate simplified management of the system 500.For example, by reducing the data protection system down to a single keyring 518, the system can eliminate or reduce the overhead for managementof keys 516. In one aspect, all of the data on a key ring 518 isprotected by one root key 526. By reducing the data protection systemdown to a single key ring 518 protected by one root key 526, allprivileged users 512 on uncompromised platforms can have access to allprotected data. In this embodiment, data is either ‘IN’ (i.e.,encrypted), or it's ‘OUT’ (i.e., not encrypted). In one aspect, thedefault system does not include any additional shade of access control.

The cryptography library 524 may be disposed on the administration host504 as shown in FIG. 5 . The cryptography library 524 may also bedisposed on the endpoint 502, e.g., in a web browser, or it may bedisposed on another component of the system 500, or any combination ofthese. The cryptographic library 524 may be installed by anadministrator. In general, key material 530 from the key ring 518 may bestored in a cache 532 on the endpoint 502 within any suitable memory onthe endpoint 502 for use in encryption and decryption as contemplatedherein. As noted above, an enterprise that systematically uses coloringand indications of compromise can be improved through the use of a keymanagement system as contemplated herein. This system may be stillfurther improved with the addition of a heartbeat system thatcommunicates heartbeats from an endpoint containing health and statusinformation about the endpoint. A suitable heartbeat system is nowdescribed in greater detail.

FIG. 6 illustrates a threat management system using heartbeats. Ingeneral, a system 600 may include an endpoint 602, a gateway 604, athreat management system 606, and an enterprise management system 608that manages an enterprise including the endpoint 602, the gateway 604,and one or more additional endpoints 610. Each of these components maybe configured with suitable programming to participate in the detectionand remediation of an advanced persistent threat (APT) or other malwarethreat as contemplated herein. Although the term “gateway” is used forthe device between an endpoint and an external network, it will beappreciated that this device may also or instead include a switch,router, firewall, and/or other network elements, any of which may beincluded in the “gateway” as that term is used herein.

The endpoint 602 may be any of the endpoints described herein, or anyother device or network asset that might join or participate in anenterprise network. The endpoint 602 may contain a threat 612 such as anadvanced persistent threat, virus, or similar malware that resides onthe endpoint 602. The threat 612 may have reached the endpoint 602 in avariety of ways, and may have been placed manually or automatically onthe endpoint 602 by a malicious source. It will be understood that thethreat 612 may take any number of forms and have any number ofcomponents. For example, the threat 612 may include an executable filethat can execute independently, or the threat 612 may be a macro,plug-in, or the like that executes within another application.Similarly, the threat 612 may manifest as one or more processes orthreads executing on the endpoint 602. The threat 612 may install from afile on the endpoint 602 or a file remote from the endpoint 602, and thethreat 612 may create one or more other files such as data files or thelike while executing. Advanced persistent threats can be particularlydifficult to detect and remediate, and the systems and methodscontemplated herein can advantageously provide improved sensitivity tosuch threats, as well as enabling improved remediation strategies.However, the systems and methods contemplated herein may also or insteadbe used to detect and remediate other types of malware threats. As such,in this context references to a particular type of threat (e.g., anadvanced persistent threat) should be understood to generally includeany type of malware or other threat to an endpoint or enterprise unlessa more specific threat or threat type is explicitly provided orotherwise clear from the context.

The threat 612 may be analyzed by one or more threat countermeasures onthe endpoint 602 such as a whitelisting filter 614 that approves eachitem of code before executing on the endpoint 602 and prevents executionof non-whitelisted code. The endpoint 602 may also include an antivirusengine 616 or other malware detection software that uses any of avariety of techniques to identify malicious code by reputation or othercharacteristics. A runtime detection engine 618 may also monitorexecuting code to identify possible threats. More generally, any of avariety of threat detection techniques may be applied to the threat 612before and during execution. In general, a threat 612 may evade theseand other security measures and begin executing as a process 620 on theendpoint 602.

Network traffic 622 from the process 620 may be monitored and logged bya traffic monitor 624 on the endpoint 602. The traffic monitor 624 may,for example, log a time and a source of each network request from theendpoint 602. Where the endpoint 602 is within an enterprise network,the network traffic 622 may pass through the gateway 604 in transit to adata network such as the Internet. While the gateway 604 may belogically or physically positioned between the endpoint 602 and anexternal data network, it will be understood that other configurationsare possible. For example, where the endpoint 602 is associated with anenterprise network but operating remotely, the endpoint 602 may form aVPN or other secure tunnel or the like to the gateway 604 for use of athreat management system 606, enterprise management system 608, and anyother enterprise resources.

The endpoint 602 may use a heartbeat 626 to periodically and securelycommunicate status to the gateway 604. The heartbeat 626 may be createdby a health monitor 628 within the endpoint 602, and may be transmittedto a remote health monitor 630, for example, at the gateway 604. Thehealth monitor 628 may monitor system health in a variety of ways, suchas by checking the status of individual software items executing on theendpoint 602, checking that antivirus and other security software is upto date (e.g., with current virus definition files and so forth) andrunning correctly, checking the integrity of cryptographic key stores,checking for compliance with enterprise security policies, and checkingany other hardware or software components of the endpoint 602 asnecessary or helpful for health monitoring. The health monitor 628 maythus condition the issuance of a heartbeat 626 on a satisfactory statusof the endpoint 602 according to any suitable criteria, enterprisepolices, and other evaluation techniques. The remote health monitor 630may also or instead be provided at the threat management facility 650,for example as part of the threat management system 606 or theenterprise management system 608.

The heartbeat 626 may be secured in any suitable manner so that thehealth monitor 630 can reliably confirm the source of the heartbeat 626and the status of the endpoint 602. To this end, the heartbeat 626 maybe cryptographically signed or secured using a private key so that themonitor 630 can authenticate the origin of the heartbeat 626 using acorresponding public key. In one aspect, the heartbeat 626 may include acombination of plaintext information and encrypted information, such aswhere the status information for the endpoint is provided in plaintextwhile a digital signature for authentication is cryptographicallysecured. In another aspect, all of the information in the heartbeat 626may be encrypted.

In one aspect, a key vault 632 may be provided on the endpoint tosupport cryptographic functions associated with a secure heartbeat. Anobfuscated key vault 632 may support numerous useful functions,including without limitation, private key decryption, asymmetricsigning, and validation with a chain of trust to a specific rootvalidation certificate. A variety of suitable key management andcryptographic systems are known in the art and may be usefully employedto a support the use of a secure heartbeat as contemplated herein. Thesystem may support a secure heartbeat in numerous ways. For example, thesystem may ensure that signing and decryption keys can only be used inauthorized ways and inside an intended Access Control mechanism. Thesystem may use “anti-lifting” techniques to ensure that a signing keycan only be used when the endpoint is healthy. The system may ensurethat attacking software cannot, without first reverse-engineering thekey vault 632, extract the original key material. The system may alsousefully ensure that an attacker cannot undetectably replace the publickeys in a root certificate store, either directly or indirectly, such asin an attack that tries to cause the code to validate against adifferent set of root keys without directly replacing any keys in theroot store.

A robust heartbeat 626 may usefully provide defensive mechanisms againstreverse engineering of obfuscated content (e.g., the private keymaterial stored in key vault 632, the code used to validate the correctrunning of the remainder of the systems as part of the heartbeat 626code itself) and any anti-lifting protections to prevent malware fromdirectly using the endpoint 602 (or the health monitor 628 on theendpoint 602) to continue to send out signed heartbeat packets (e.g.stating that “all is well” with the endpoint) after security mechanismshave been impaired, disabled, or otherwise compromised in any way.Lifting in this manner by malicious code can be materially mitigated byproviding statistical validation (e.g., with checksums of code) of callstacks, calling processes, and core processes. Likewise, statisticalchecks as well as checksum integrations into the cryptographiccalculations may protect against code changes in the heartbeat 626 codeitself.

A variety of useful techniques may be employed to improve security ofthe key vault 632 and the heartbeat 626. For example, the system may usedomain shifting so that original key material is inferred based onhardware and software properties readily available to the key vault 632,and to ensure that key material uses non-standard or varying algorithms.Software properties may, for example, include readily determined systemvalues such as hashes of nearby code. In another aspect, the keys may bedomain shifted in a manner unique to the endpoint 602 so that the mannerof statistical validation of call stacks and core software is unique tothe endpoint 602. Further the key vault may be provisioned so that apublic key stored in the key vault 632 is signed with a certificate (orinto a certificate chain) that can be externally validated by a networkappliance or other trusted third party or directly by the healthmonitor.

The heartbeat 626 may encode any useful status information, and may betransmitted from the endpoint 602 on any desired schedule including anyperiodic, aperiodic, random, deterministic, or other schedule.Configured in this manner, the heartbeat 626 can provide secure,tamper-resistant instrumentation for status of the endpoint 602, and inparticular an indication that the endpoint 602 is online anduncompromised. A disappearance of the heartbeat 626 from the endpoint602 may indicate that the endpoint 602 has been compromised; howeverthis may also simply indicate that the endpoint 602 has been powered offor intentionally disconnected from the network. Thus, other criteria maybe used in addition to the disappearance or interruption of theheartbeat 626 to more accurately detect malicious software. Some suchtechniques are described below, but it will be understood that this mayinclude any supplemental information that might tend to make an attackon the endpoint 602 more or less likely. For example, if the heartbeat626 is interrupted but the endpoint 602 is still sourcing networktraffic, then an inference might suitably be made that the endpoint 602is compromised.

The threat management system 606 may, in general, be any of the threatmanagement systems described herein. The enterprise management system608 generally provides tools and interfaces for administration of theenterprise and various endpoints 610 and other resources or assetsattached thereto. It will be understood that, the functions of thethreat management system 606 and the enterprise management system 608may vary, and general threat management and administration functions maybe distributed in a variety of ways between and among these and othercomponents. This is generally indicated in FIG. 6 as a threat managementfacility 650 that includes the threat management system 606 and theenterprise management system 608. It will be understood that either orboth of these system may be administered by third parties on behalf ofthe enterprise, or managed completely within the enterprise, or somecombination of these, all without departing from the scope of thisdisclosure. It will similarly be understood that a reference herein to athreat management facility 650 is not intended to imply any particularcombination of functions or components, and shall only be understood toinclude such functions or components as explicitly stated in aparticular context, or as necessary to provide countermeasures foradvanced persistent threats as contemplated herein. It also should beunderstood that the heartbeat may be monitored and/or managed by thethreat management system 606, the enterprise management system 608, oranother component of the threat management facility 650.

The system 600 may include a certificate authority 660 or similar trustauthority or the like (shown as a “trusted third party” in the figure).In order to provide a meaningfully secure heartbeat 626, the heartbeat626 may be secured with reference to a trusted authority such as acertificate authority 660 that can issue cryptographic certificatesallowing other entities to rely on assertions about identity (e.g., byenabling verification with a trusted third party), and to enablecryptographically secure communications. The cryptographic techniquesfor creating and using such certificates and relationships are wellknown, and are not repeated here. The certificate authority 660 may beadministered by the enterprise management system 608 or some otherinternal resource of the enterprise, or the certificate authority 660may be administered by a trusted third party such as any of a variety ofcommercially available certificate authorities or the like. Thus, thecertificate authority 660, or some other similar cloud service or thelike, may operate as a security broker to register, e.g., endpoints 602,610, the gateway 604, the threat management facility 650, and so forth,and provide cryptographic material for each of the other trustingentities to securely communicate with one another.

Once registered with the certificate authority 660 in this fashion, theheartbeat may be used to establish trust between the endpoint 602 andother entities, and to validate the source of the heartbeat 626 when itis received. More generally, a heartbeat 626 secured in this manner mayprovide an encrypted channel between network entities such as anendpoint 602 and the gateway 604 (or a firewall or the like). The natureof the communication may provide a technique for validating the source,as well as obfuscating the contents with encryption. Thus when, forexample, the endpoint 602 provides information about a good/healthystate or a bad/compromised state, the recipient may rely on this stateinformation and act accordingly.

FIG. 7 shows an architecture for endpoint protection in an enterprisenetwork security system. In general, an endpoint may include aprocessing environment 702, a file system 706, a threat monitor 720 anda key wrapper 730.

The processing environment 702 may, for example, be any environment suchas an operating system or the like suitable for executing one or moreprocesses 704.

Each process 704 may be an instance of a computer program, portion of acomputer program or other code executing within the processingenvironment 702. A process 704 may execute, e.g., on a processor, groupof processors, or other processing circuitry or platform for executingcomputer-executable code. A process 704 may include executable computercode, as well as an allocation of memory, file descriptors or handlesfor data sources and sinks, security attributes such as an owner and anyassociated permissions, and a context including the content of physicalmemory used by the process 704. More generally, a process 704 mayinclude any code executing on an endpoint such as any of the endpointsdescribed herein.

The file system 706 is generally associated with an operating systemthat provides the processing environment 702, and serves as anintermediary between processes 704 executing in the processingenvironment 702 and one or more files 708 stored on the endpoint. Thefile system 706 may provide a directory structure or other construct tofacilitate organization of the files 708, and the file system 706generally supports file functions such as creating, deleting, opening,closing, reading, writing, and so forth.

An extension 710 may be included in the file system 706 by modifying theoperating system kernel. While other programming techniques may beemployed to perform the functions of an extension 710 as contemplatedherein, direct modifications of or additions to the operating systempermit the extension 710 to operate transparently to the processingenvironment 702 and the processes 704 without requiring anymodifications or adaptations. The extension 710 may, for example, beimplemented as a file system filter (in a MICROSOFT WINDOWS environment)or a mount point to a directory (in an APPLE iOS environment). Theextension 710 to the files system as contemplated herein performs twoconcurrent functions. First, the extension 710 communicates with athreat monitor 720 in order to receive updates on the security statusand exposure status of the processes 704 or the endpoint. Second theextension 710 communicates with a key wrapper 730 that provides keymaterial for encrypting and decrypting data in the files 708. Finally,the extension 710 operates to conditionally provide encryption anddecryption of the files 708 for the processes 704 based on a currentsecurity or exposure state, as described in greater detail below.

The threat monitor 720 may include any suitable threat monitoring,malware detection, antivirus program or the like suitable for monitoringand reporting on a security state of an endpoint or individual processes704 executing thereon. This may include local threat monitoring using,e.g., behavioral analysis or static analysis. The threat monitor 720 mayalso or instead use reputation to evaluate the security state ofprocesses 704 based on the processes 704 themselves, source files orexecutable code for the processes 704, or network activity initiated bythe processes 704. For example, if a process 704 requests data from aremote URL that is known to have a bad reputation, this information maybe used to infer a compromised security state of the endpoint. While athreat monitor 720 may operate locally, the threat monitor 720 may alsoor instead use remote resources such as a gateway carrying traffic toand from the endpoint, or a remote threat management facility thatprovides reputation information, malware signatures, policy informationand the like for the endpoint and other devices within an enterprisesuch as the enterprise described above.

In general, the threat monitor 720 provides monitoring of a securitystate and an exposure state of the endpoint. The security state may, forexample, be ‘compromised’, ‘secure’, or some other state or combinationof states. This may be based on detections of known malware, suspiciousactivity, policy violations and so forth. The exposure state may be‘exposed’ or ‘unexposed’, reflecting whether or not a particular process704 or file 708 has been exposed to potentially unsafe content. Thusexposure does not necessarily represent a specific threat, but thepotential for exposure to unsafe content. This may be tracked in avariety of ways, such as by using the coloring system described abovewith reference to FIG. 5 .

The key wrapper 730 may contain a key ring 732 with one or more keys 734for encrypting and decrypting files 708. The key ring 732 may becryptographically protected within the key wrapper 730 in order toprevent malicious access thereto, and the key wrapper 730 maycommunicate with the extension 710 to provide keys 734 for accessing thefiles 708 at appropriate times, depending, for example, on whetherprocesses 704 are secure or exposed. In one aspect, the files 708 arestored in a non-volatile memory such as a disk drive, or in a randomaccess memory that provides a cache for the disk drive, and the keywrapper 730 may be stored in a separate physical memory such as avolatile memory accessible to the operating system and the extension 710but not to processes 704 executing in the user space of the processingenvironment 702.

In one aspect, every document or file on the endpoint may have aseparate key. This may be, for example, a unique, symmetric key that canbe used for encryption and decryption of the corresponding file. The keywrapper 730 may control access to the key material for encrypting anddecrypting individual files, and may be used by the extension 710 tocontrol access by individual processes 704 executing on the endpoint. Asdescribed herein, the extension 710 may generally control access tofiles 708 based on an exposure state, a security state, or other contextsuch as the user of a calling process or the like. In the event of asevere compromise, or a detection of a compromise independent ofparticular processes, a key shredding procedure may be invoked todestroy the entire key wrapper 730 immediately and prevent any furtheraccess to the files 708. In such circumstances, the keys can only berecovered by the endpoint when a remediation is confirmed.Alternatively, the files may be accessed directly and decrypted from asecure, remote resource that can access the keys 734.

FIG. 8 shows a method for labeling network flows. In general, networkflows may be explicitly labeled according to source applications (orsource processes or the like) to permit tracking and managementaccording to a source after a network flow leaves an endpoint.

As shown in step 802, the process 800 may include executing a process onan endpoint, such as any of the endpoints described herein. The process800 may, for example, be associated with an application on the endpoint.

As shown in step 804, the process 800 may, at some point during itsexecution, create a network message. In general, a network message mayinclude a header containing, e.g., a source address, a destinationaddress, and other information necessary or helpful for supporting datanetwork communications between the endpoint and an intended destination.The network message may, for example, be in response to an explicit userinput such as directing a browser to a web address, or in response to animplicit user input such as requesting a software update or performingan online backup. This may also or instead be fully automated under anyof a variety of normal circumstances. This may also, however, beoutbound traffic from malware, and by labeling the network traffic,malicious activity may be more easily detected after the network messagehas left the endpoint.

As shown in step 806, the process 800 may include adding a label to thenetwork message. This may, for example, include generating a label thatincludes context information related to the network message, such as anidentifier for an application or process. This identifier may becryptographically signed or encrypted to protect the contents thereof,and may include additional information about, e.g., the status of theendpoint, the reputation of the application or the destination address,or any other information necessary or helpful for making improvedrouting or processing decisions about network traffic. Thus, the process800 may include cryptographically signing the label, encrypting thecontents of the label, or any other suitable cryptographic steps. Packetstructures for network communication are generally known, and may forexample include a header with control and routing information, alongwith a payload of data for communication to a recipient. The header mayinclude various items of information useful for network communicationssuch as a preamble that identifies a beginning of the packet, a sourceaddress, a destination address, a sequence number (e.g., for spreading alarge file or the like across multiple packets/payload), a packetlength, a packet type, a cyclic redundancy check or other checksum orthe like, and any other useful information. A label as contemplatedherein may be usefully incorporated into the header of such a packet inany suitable format and any suitable location. For example, internetprotocol version ‘4’ and version ‘6’ both permit optional information tobe included in a packet, and the label may be included as optionalinformation. For example, the label may be included by encapsulating apacket within another packet that includes label information. Forexample, a label may be included by repurposing a portion of a packetheader. For example, a label may be included by injecting additionallabel data into the packet, or for example, at the start of the dataportion of the packet.

As shown in step 808, the process 800 may include transmitting thenetwork message from the endpoint, e.g., through a network interface orthe like to a data network.

According to the foregoing, in one aspect there is disclosed herein anendpoint configured as described above to label outbound networkmessages to identify a source process or application. Thus there isdisclosed herein a system comprising an endpoint including a networkinterface configured to couple the endpoint in a communicatingrelationship with a data network. The endpoint may include a memory anda processor such as any of the memories, processors, or processingcircuitry described herein. In general, the processor may be configuredto execute instructions stored in the memory to perform the steps ofgenerating a label for a network message created by a process executingon the endpoint and associated with an application, where the networkmessage includes a payload and a header and where the label includes anidentifier for the application, adding the label to the header of thenetwork message, and transmitting the network message through thenetwork interface to a remote location on the data network. At the sametime, a network device or the like may be configured to receive thenetwork message and process it in a variety of ways, as furtherdiscussed herein.

As shown in step 810, the process 800 may include receiving a networkmessage from an endpoint at a network device. The network message may bethe network message described above, or any other packet or other datastructure including a payload of data and header information such as asource address for the endpoint and a destination address for anintended recipient of the network message. The network message may alsoinclude a label that identifies an application that generated thenetwork message on the endpoint. This may for example, be determined byexamining the properties of a process associated with the application,or otherwise relating a process or other source of the network messagewith a particular application.

It should be understood that this receiving step may be performed at awide range of network devices. In one aspect, this may include a router,a gateway, a firewall, a threat management facility for an enterprise,or any other network device for handling network communications toand/or from the endpoint. This may include a network device on a localnetwork used by the endpoint, a cloud-based network device used in anenterprise network security system, a physical gateway between anenterprise network and an external network, or some combination ofthese. In one aspect, the firewall may be a local firewall for theendpoint that is configured to locally enforce routing rules based oninformation obtained in the label.

While a source application may be a useful item of information to beincluded in the label, it will be understood that other contextinformation may also or instead be included. For example, this mayinclude the identity of a process of an application that created thenetwork message, a user of the process that created the network message,or other identity or source information, such as a name or otheridentity of the endpoint. For the endpoint name this may include a fullyqualified name such as a device identifier that is unique within thedomain of the endpoint. This may also or instead include a reputation ofthe application or process that created the network message if this islocally available to or determined by the endpoint. In this context, thereputation may specify a particular reputation (e.g., known good, knownbad, suspected bad, or the like) or the reputation may specify anabsence of specific information (e.g., unknown). This may also orinstead include health information about the endpoint or a process,coloring information for the process that identifies exposure of theprocess to other processes or data on the endpoint, reputation orexposure information for data used by the process, and so forth. Thelabel may include status information related to the endpoint, such as anactivity level of the endpoint, a status of software installed on theendpoint, a security condition of the endpoint (e.g., anti-malwaresoftware installed, a warning state of control software, and so forth),or other useful status indications in evaluating context of the networktraffic and the like.

It should also be understood that, while the process 800 describedherein may involve proactive labeling of network flows, or labeling ofall network flows from an endpoint, the process 800 may also or insteadbe adapted to be responsive to detection and query by a network device,such as a threat management facility, a firewall, a gateway, a server,or the like. For example, a malware attack that exfiltrates data maybegin with a file upload using a file transfer protocol (FTP) request oran HTTP PUT. When upload activity from the endpoint is detected at anetwork device, this may cause the network device to actively query theendpoint to request information about the application that requested theupload, such as an identifier of the application, a reputation of theapplication, or the like. For example, the network device may direct theendpoint to label all traffic from a user, from an application, from aprocess, or from a device. For example, the network device may directthe endpoint to label all traffic from processes that are currentlyactive. For example, the network device may direct the endpoint to labelall traffic from users that are currently active. For example, thenetwork device may direct the endpoint to label all traffic from a userassociated with a process. For example, the network device may firstdirect the endpoint to label all network traffic to identify a process.The network device may then identify a process of interest, and directthe endpoint to label all traffic associated with the process ofinterest, or associated with a user associated with the process ofinterest. These and other similar adaptations are intended to fallwithin the scope of this disclosure.

The process may also or instead be adapted to be responsive to detectingsuspicious activity at the endpoint. Upon detecting suspicious activity,the endpoint may begin to label network traffic associated with thesuspicious activity. The label may indicate that the labeled networktraffic is associated with suspicious activity. The label may provideadditional context for the network traffic and associated application orprocess. A network device receiving labeled network traffic from anendpoint may then take additional measures, such as observing andrecording the content of the network traffic, inspecting the content ofthe network traffic, verifying the reputation of the destination(s) ofthe network traffic, verifying the reputations of the application(s)generating the network traffic, determining whether there is othernetwork traffic from other devices on the network directed to thedestination, notifying an administrator, and so on.

The process may also or instead be adapted to be responsive to detectingsuspicious activity at an endpoint that hosts one or more virtualmachines. Upon detecting suspicious activity, the endpoint may labelnetwork traffic with context associated with the virtual machine. Forexample, the label may include an identifier for the virtual machine,e.g., if the virtual machine is not using a unique network address. Thelabel may indicate that the labeled network traffic is associated withsuspicious activity. The label may provide additional context for thenetwork traffic and associated application or process. A network device,or a virtual machine host, or another virtual machine on the same hostthat is receiving labeled network traffic from the virtual machine, maythen take additional measures.

The process may also or instead be adapted to be responsive to detectingsuspicious activity at a network device. Upon detecting suspiciousactivity, the first network device may begin to label network trafficassociated with the suspicious activity. The label may indicate that thelabeled network traffic is associated with suspicious activity. Thelabel may provide additional context for the labeled network trafficthat may be available at the network device, for example, that thetraffic transited the network device, or came from a particular subnet,or was recorded by the network device. The label may provide a referenceto additional information collected by the network device about thesuspicious network traffic. For example, the reference may be to arecording of the content of the network traffic. A network devicereceiving labeled network traffic from an endpoint may then takeadditional measures, such as observing and recording the content of thenetwork traffic, inspecting the content of the network traffic,verifying the reputation of the destination(s) of the network traffic,verifying the endpoint(s) generating the network traffic, determiningwhether there is other network traffic from other devices on the networkdirected to the destination, notifying an administrator, and so forth.

As shown in step 812, the process 800 may include processing the networkmessage on a network device that receives the network message to extractthe label. This may, for example, include cryptographically verifying anauthenticity of the label or a source of the label, decrypting the labelto extract encoded information, or any other form of processing.

As shown in step 814, the process 800 may include processing the networkmessage at a network device based on the label. While routing isgenerally contemplated as described below, a number of additionalprocessing steps may usefully be performed. For example, the process 800may include caching the label, for example associated with theapplication and a reputation of the application on the network device.

As shown in step 816, the process 800 may include routing the networkmessage based on the application (or process or other source on theendpoint) that generated the network message. The routing may be aconditional routing based on the information in the label, orinformation determined from the information in the label. This mayinclude routing rules or combinations of rules that may be based, forexample, on user identity, process/application, reputation, and soforth. For example, the processor may be further configured to performthe steps of determining a reputation of the application and routing thenetwork message to the destination address conditionally based on thereputation of the application that generated the network message. Thatis, if the reputation of the application is known and good, then thetraffic may be routed as requested by the endpoint according to therouting information in the network traffic. However, if the reputationof the application is known and bad, then the traffic may be sequesteredin any suitable manner. For example, the traffic may be dropped.Additional steps may be taken. For example, when the reputation of theapplication is uncertain, or other information is collectivelyinconclusive, a sandbox based on the endpoint may be created and used tocommunicate with the destination address to test for malicious activity.In another aspect, where information is inconclusive, the networktraffic may be permitted, but more aggressive monitoring may beinitiated until a conclusive evaluation of the source application can beobtained. For example, the network device may observe and record thenetwork traffic, inspect the content of the network traffic, verify thereputation of the destination(s) of the network traffic, verify thereputations of the application(s) generating the network traffic,determine whether there is other network traffic from other devices onthe network directed to the destination, notify an administrator, and soforth. In another aspect, an indication of malware or other compromiseon the endpoint may be used as a basis for initiating remediation of theendpoint.

Likewise, in the case of uncertain application reputation, some usersmay have additional permissions with respect to network traffic routingdecisions. For example, a user designated as an accounting user, who mayhave access to more sensitive information may have traffic blocked,while a user in sales or customer support may be permitted withadditional monitoring or safeguards.

In this context, it will be appreciated that an application or processidentifier in the label may be used as a single item of information in abroader context for the network message. For example, the label mayinclude a health status of the endpoint, other status information of theendpoint, a user identifier for a user of the application or a relatedprocess (e.g., automated machine activity—e.g., daemon, backupservice—might be treated differently from human activity, categories ofusers may be treated differently than others, and the like), a name ofthe endpoint, reputation information for the source application, and soforth. Thus, the application identifier may be useful by itself, but theaccuracy of attack detection may be improved still further by usingadditional context for the network message, which may include variouspieces of contextual information inserted directly into the label forthe network message, as well as other information available to a networkdevice called upon to make a routing decision for a particular networkmessage (e.g., allowing, blocking, rerouting, and so forth). The routingdecision may include blocking the message. All such variations thatwould be apparent to one of ordinary skill in the art are intended tofall within the scope of this disclosure.

According to the foregoing, there is disclosed herein a system thatincludes a network device that may use labels provided by endpoints thatidentify source applications or processes and the like for networkmessages. In one aspect, a system disclosed herein includes a networkdevice including a network interface configured to couple the networkdevice in a communicating relationship with a data network that includesan endpoint, a memory on the network device, and a processor on thenetwork device. The processor may be configured to execute instructionsstored in the memory to perform the steps of receiving a network messagefrom an endpoint through the network interface, where the networkmessage includes a source address for the endpoint, a destinationaddress for an intended recipient of the network message, a label thatidentifies an application that generated the network message on theendpoint, and a payload of data. The processor may be further configuredto execute instructions stored in the memory to perform the steps ofprocessing the network message to extract the label, and routing thenetwork message based on the application that generated the networkmessage.

In one use of this system, the processor may be configured to determinea reputation of the application and to route the network message to thedestination address conditionally based on the reputation of theapplication that generated the network message, for example as describedabove. Where information such as user information is available, theprocessor may be further configured to extract a user identifier fromthe label that identifies a user of the application on the endpoint,which may also be usefully employed for various intelligent routingprocesses as contemplated herein.

FIG. 9 illustrates an Internet Protocol (IP) packet format. In general,the packet 900 may include preamble information 902, a source address904, a destination address 906, option information 908, and a payload ofdata 910. As described herein, the source address 904 may generallyspecify a network location that originated the packet 900, but may notprovide any more specific information about a source user, a sourcemachine, a source application, and other information as contemplatedherein.

In one aspect, this information may be usefully added to the packet 900by inserting relevant information into the option information 908, or inany other suitable location within the packet 900 or packet header. Forexample, the Internet Protocol version ‘4’ (IPv4) packet may beconfigured such that additional information may be included in thepacket header, which may be specified by the internet header length(IHL) data and an option type field. This field is identified in FIG. 9as option information 908. In ordinary use, the option type field issub-divided into a one bit copied flag, a two bit class field, and afive bit option number. These taken together form an eight bit value forthe option type field. In one aspect, this field may be used to specifyadditional source information, or to identify a link or pointer to alocation where such information can be obtained. For example, up to 60bytes of optional, additional data may be included in the header, and alabel may be included in this additional data. For example, where thepacket is used within an enterprise domain, a portion of the header maybe used by any source-aware networking components to identify a source,or to provide a pointer to source information which may, for example, bewithin the data 910 of the packet 900, within a separate packet, orstored at a network-accessible location such as a gateway, firewall, orthreat management facility. An internet protocol version ‘6’ (IPv6)packet may include a 20-bit flow label field, as well as theavailability to provide extension headers to indicate optionalinformation. For example, the flow label field may be used to include a20-bit label. For example, a ‘Destination Options’ extension header maybe used to include label information that is not required to be examinedby intermediate networking devices, but may be examined by a gateway ora final destination.

In one aspect, the option information 908 of an IPv4 packet may be usedto designate the packet as containing source information 912 within thedata 910 of the packet 900. Thus, for example, the first byte or bytesof the data 910 may be used to specify source information at any desiredlevel of granularity including a user, a machine, an application, aprocess, and so forth, as well as combinations of these. The sourceinformation 912 within the data 910 may also or instead provide a linkto a resource within the enterprise network where source information forthe packet 900 can be retrieved. It will be understood that sourceinformation, whether stored within source information 912 in the packet900, within the option information 908 in the packet header 914, orstored in some remote resource, may in general be encrypted to securesource information against unauthorized access, and/or the sourceinformation may be digitally signed to permit verification ofauthenticity with reference to a trusted third party or internal trustauthority.

In one aspect, source information 912 may include a reference to aprocess or other context information for an endpoint. The endpoint maycommunicate context information to a network device through a separatechannel, for example using the heartbeat 314 channel (see, e.g., FIG. 3). The context information may be stored on the endpoint, and the sourceinformation 912 in the packet 902 may include a reference to the contextinformation. Thus, context information may be provided via a firstchannel, and a reference to the context information may be provided in apacket label. For example, each process on an endpoint may be assignedan identifier, and the identifier communicated to the network devicewith the operating system process information when the process isdetected. The identifier may be included in the label. In this way,machine-specific information may not be included in the packet, but onlya reference to the information. In some implementations, the identifieris changed periodically.

A flag within the packet header 914 may also or instead be used toidentify when (and where) source labeling information is present for apacket 900.

In one aspect, the packet 900 may be configured to be compatible withother IP network traffic, so that packets can move into and out of theenterprise network without additional handling, such as by insertingsource information 912 into the data 910 of the packet payload asillustrated in FIG. 9 . In another aspect, packets may be processed atthe perimeter of the enterprise network, e.g., at a VPN gateway,enterprise network gateway, or any other perimeter network device, orother suitable router, switch, or other network device inside theenterprise network, with non-IP compliant packet data and/or structuresbeing removed for outbound traffic, and where possible or applicable,reinserted for inbound traffic. In another aspect, traffic from outsidethe enterprise network may use a predetermined flag or the like toindicate that a packet contains source information compliant with aformat for source information used within the enterprise network. Moregenerally, any suitable techniques may be used to permit communicationof source context information with network traffic within a network,while ensuring compatibility with an external network architecture suchas TCP/IP or the like, and all such techniques that would be apparent toone of ordinary skill in the art are intended to fall within the scopeof this disclosure.

FIG. 10 shows a method for secure labeling of network flows. A systemfor labeling network flows is generally described herein (e.g., above).A network enterprise security system may be improved by instrumentingendpoints to explicitly label network flows with cryptographicallysecure labels that identify an application or other source of eachnetwork flow. Cryptographic techniques may be used, for example, toprotect the encoded information in the label from interception by thirdparties or to support cryptographic authentication of a source of eachlabel. As discussed above, a label may provide health, status, or otherheartbeat information for the endpoint, and may be used to identifycompromised endpoints, to make routing decisions for network traffic(e.g., allowing, blocking, or re-rerouting), to more generally evaluatethe health of an endpoint that is sourcing network traffic, or for anyother useful purpose.

As shown in step 1002, the method 1000 may include receiving a networkmessage from a process executing on the endpoint. In general, theprocess may be based on an application on the endpoint. As describedherein, the network message may be a packet or the like that includes apayload and a header, and that is addressed to a remote location (e.g.,using an Internet Protocol address, Uniform Resource Locator (URL), orother address) accessible from the endpoint through a data network.

As shown in step 1004, the method 1000 may include generating a labelfor the network message. As described herein, the label may includeinformation about a source of the network message on the endpoint, e.g.,an application, a process, a user or the like on the endpoint thatoriginated the network message, or an identity of the endpoint itself,such as by reference to a globally unique name of the endpoint within anenterprise domain. Thus, for example, the label may include anidentifier for the application that generated the network message, anidentifier for the endpoint that generated the network message, theidentifier of a user of the process on the endpoint that generated thenetwork message, or any other useful source identifier. The label mayalso or instead encode useful information about the status of theendpoint. For example, the label may include a health status of theendpoint or any other useful information.

As shown in step 1005, the method 1000 may include cryptographicallyprocessing the label information. This may, for example, includecryptographically signing the label to provide a signed labelinformation. This signed label may be used, for example, to verify anidentity of the endpoint, an identity of an application on the endpoint,an identity of a process executing on the endpoint, or any combinationof these that is useful for identifying a source of the network message.This signed label may be verified, for example, using a public key forthe source that is signing the label, or through any other suitablerelationship with a trusted third party capable of cryptographicallyauthenticating the source. Cryptographically processing the networkmessage may also or instead include encrypting the label with acryptographic key to provide an encrypted label that is secured againstinterception by third parties.

As shown in step 1006, the method 1000 may include adding thecryptographically process label (e.g., the signed label and/or encryptedlabel) to the header of the network message.

As shown in step 1008, the method 1000 may include transmitting thenetwork message from the endpoint to the remote location through thedata network.

As shown in step 1010, the method may include receiving the networkmessage from the endpoint at a network device such as a gateway, afirewall, a router, a switch, or a threat management facility, any ofwhich may be a hardware device physically positioned between theendpoint and an external data network, or a cloud-based deviceaccessible to the enterprise network for the endpoint through a remoteservice or resource. The network message may be any of the networkmessages described herein, and may include an encrypted label thatidentifies an application that generated the network message, and/or asigned label that can be used to verify a source or the security of thelabel.

As shown in step 1011, the method 1000 may include processing thenetwork message on the network device to extract the label.

As shown in step 1012, the method may include cryptographicallyprocessing the label. This may, for example, include verifying a sourceof the label or decrypting the label with a cryptographic key to providea decrypted label.

As shown in step 1014, the method 1000 may include processing thenetwork message based on the label, for example, by caching label orpayload contents on the network device, requesting a scan or remediationof the endpoint that provided the message, or any other responsiveprocessing. This may, for example, include receiving an indication thatthe endpoint is compromised, e.g., either embedded within the label orthrough another communication channel. For example, the network devicemay receive a heartbeat from the endpoint, and the indication ofcompromise may be inferred from an absence of the heartbeat whenexpected, or the indication of compromise may be explicitly added by theendpoint (e.g., by a security agent executing on the agent) into theheartbeat. This indication of compromise may be used as a basis forpreventing routing of additional network traffic from the compromisedapplication through the network device. This routing or forwardingrestriction may be maintained, for example, until the expected heartbeatresumes from the endpoint/application, or until an explicit remediationmeasure is completed.

By labeling network flows by application in this manner, the networkdevice that is handling the network flow can advantageously make routingor blocking decisions on an application-by-application basis rather thanfor an entire endpoint, thus limiting network restrictions to particularapplications that are compromised while permitting other applications onan endpoint to continue normal network communications, or optionallynetwork communications with some heightened level of scrutiny orsecurity.

As shown in step 1016, the method 1000 may include routing the networkmessage based on the decrypted label, for example using any of thetechniques described herein.

According to the foregoing, there is disclosed herein a system forsecure labeling of network flows. The system may include an endpointincluding a network interface configured to couple the endpoint in acommunicating relationship with a data network, a memory on theendpoint, and a processor on the endpoint. The processor may beconfigured as described herein to execute instructions stored in thememory to perform the steps of receiving a network message from aprocess executing on the endpoint, where the process is based on anapplication and where the network message includes a payload and aheader. The network message may be addressed to a remote locationaccessible from the endpoint through a data network. The processor mayfurther be configured to execute instructions stored in the memory toperform the steps of generating a label for the network message, wherethe label includes information about a source of the network message onthe endpoint, encrypting the label with a cryptographic key, therebyproviding an encrypted label, adding the encrypted label to the headerof the network message, and transmitting the network message from theendpoint to the remote location through the data network. Encrypting thelabel may include cryptographically signing the label or otherwisecryptographically processing the label as described herein.

FIG. 11 shows a process for verifying user presence on an endpoint. Ingeneral, a gateway or other network device may be configured to monitorendpoint behavior, and to request a verification of user presence at theendpoint under certain conditions suggesting, e.g., malware or otherendpoint compromise. For example, when a network request is directed toa low-reputation or unknown network address, user presence may beverified to ensure that this action was initiated by a human user ratherthan automatically by malware or the like. User verification may beimplicit, based on local behavior such as keyboard or mouse activity, orthe user verification may be explicit, such as where a notification ispresented on a display of the endpoint requesting user confirmation toproceed.

As shown in step 1102, the method 1100 may include connecting anendpoint to a data network through a gateway.

As shown in step 1104, the method 1100 may include detecting a networkrequest at the gateway by a process executing on the endpoint. Thenetwork request may, for example, include any of the network messagesdescribed herein, or any other network request or the like. By way ofnon-limiting example, the network request may include a request for adownload of an executable from a data network, an HTTP PUT request orother a request to an address contained in a Uniform Resource Locatorentered, e.g., in a browser or similar application, an FTP file transferrequest, or any other manually or automatically generated networkrequest. It will be understood that in the context of this method 1100,this step 1104 may refer specifically to the detection or otheridentification of a network request that presents a potential or actualsecurity risk, or other indication of compromise or the like. While itis also possible to test for the presence of a human user under othercircumstances, the remaining steps disclosed in this method 1100 relateto a context in which the network message poses a potential risk. Thusfor example, the network request may be directed to a remote resourcethat presents a potential security risk such as a remote resource with alow or unknown reputation, or a remote resource known to be associatedwith malware distribution or the like. This may also or instead includea network request directed to an unknown address or a request directedto a known or suspected source of malware. The potential security riskmay also be identified contextually, such as by detecting a pattern ofconnections to a single resource, an unusual sequence of destinationaddresses, or some other network activity (or other endpoint behavior)indicative of potential compromise of the endpoint.

As shown in step 1105, once potentially harmful network traffic isdetected, other steps may be taken to provide additional context forevaluation or to reach a conclusion on further action before evaluatinguser presence. For example, the method 1100 may include requesting areputation of an application on an endpoint that initiated the networkrequest. This may permit direct blacklist or whitelist determinations orthe like without requiring additional queries to the endpoint. This mayalso be particularly useful for identifying circumstances where humanpresence may be highly relevant to the detection of a security risk. Forexample, where a connection is opened to a remote location of low orunknown reputation and an upload of data from the endpoint to the remotelocation is initiated, this pattern would suggest malicious data leakageor exfiltration, and it may be highly advantageous to determine whethera human user is controlling the activity by the endpoint. Similarly,certain protocols that are commonly used to download malware (e.g., peernetworking protocols) or upload sensitive data (e.g., a file or datatransfer protocol) may provide useful context for an initial decisionwhether to test for the presence of a human user.

As shown in step 1106, the method 1100 may include evaluating a statusof the endpoint to determine whether a user is present at the endpoint.In particular, if there is a reason to suspect the network request posesa potential security risk, or if there are other indicia of compromisefor the endpoint, then a procedure may be initiated to evaluate whethera human user is present on the endpoint and/or whether a human userinitiated the network request. Thus for example, evaluating the statusmay include querying the endpoint about whether the user is present.Evaluating the status may also or instead include transmitting a requestto the endpoint for a user input. For example, the request may bepresented as a pop-up window or other notification with text requestinga response. This may include a simple request such as “click here tocontinue,” or a more instructive narrative such as: “A potentialsecurity issue has been detected. Please click here to confirm that yourequested the following network activity.” This may also or insteadinclude other user input besides clicking, e.g., typing characters intoa text box or the like. In another aspect, a blocking page may bepresented in a web browser that requires human interaction beforefurther network activity can be undertaken.

In another aspect, the presence of a human user may be inferred fromendpoint activity or status. For example, information about useractivity or user presence may be included in a secure heartbeat from theendpoint, and evaluating the status may include examining the secureheartbeat from the endpoint for information about whether the user ispresent. The status of the endpoint may include other state informationor historical activity indicative of user presence. For example, thestatus may include whether a user is logged in to the endpoint (whichsuggests that a human user is presently using the endpoint) or whether adisplay of the endpoint is locked (which suggests that a human user isnot presently using the endpoint). The status may also or insteadinclude other information useful for inferring whether the user ispresent. For example, the status may include a record of keyboard ormouse activity within a predetermined time window such as a priorminute, a prior five minutes, a prior ten minutes, and so forth.

In another aspect, the inquiry may include evaluating whether a user waspresent when the application that generated the network request waslaunched, which may be relevant in a number ofcircumstances—particularly where a user might initiate a large onlinebackup or other lengthy download or upload procedure—where a user mightintentionally initiate network activity and then log out from anendpoint.

In another aspect, the inquiry may simply include verifying the intentof a user that is known to be present. For example, this method 1100 maybe usefully employed to prevent a pfishing attack where alegitimate-appearing electronic mail communication contains a link to amalicious site. In this use case, the application may be an electronicmail client (e.g., of presumed unsafe reputation), and the networkrequest coming from the application may be addressed to a location ofunknown reputation. In this context, even though a user is known to bepresent because of the manual link navigation, remediation may beappropriately undertaken, such as by presenting a pop-up window orblocking page that explicitly identifies the target page and requestsconfirmation of the navigation instruction. For example, thenotification may state: “You have requested access to [website]. Are youcertain that you wish to navigate to this potentially unsafe networklocation?”

This and other techniques may be used to evaluate whether a user ispresent, or whether a user intended to initiate a particular networkrequest.

As shown in step 1108, when a user is determined to be present in step1106, other processing may be performed. This may in include returningto step 1104 where additional network requests may be detected. Ofcourse, other processing, rules, or decision logic may be applied inthis context. For example, where a destination address is blacklisted orwhitelisted, a decision on forwarding the network flow may be maderegardless of whether a user is present. All such existing techniquesfor conditionally forwarding traffic, including those describedelsewhere herein may be used in addition to or instead of detecting userpresence, and a method may provide various types of threat detection andsecurity management, either concurrently, sequentially, or in some otherorder or manner, all without departing from the scope of thisdisclosure. Thus it should be appreciated that the techniques describedwith reference to FIG. 11 (and the other figures in this disclosure) maybe intended for use either alone or in combination with other techniquesfor managing network flows and protecting against security threats in anenterprise network.

As shown in step 1110, where it is determined in step 1106 that no useris present, the method 1100 may include remediation. This may includeany type of response or remediation suitable to the circumstances. Forexample, when no user is detected at the endpoint, this may includeexecuting a security measure in response to the network request such asblocking the network request, initiating a scan or remediation of theendpoint, blacklisting the destination address, updating a reputation ofthe destination address, or any other suitable action. It will beunderstood that the remediation may be contextually selected based, forexample, on other available information such as a reputation of thedestination address for the network request, or a reputation of anapplication on the endpoint making the request.

In other circumstances, no remediation may be required. For example,where both the endpoint application and the remote location areupdaters, then an endpoint that automatically requests a downloadwithout a user present may be a part of a legitimate, periodic softwareupdating protocol. Similarly, where the endpoint application and theremote location both have a known, good reputation, then the activitymay be permitted even in the absence of a human user of the endpoint.

When the remediation has been initiated or completed, the method 1100may return to step 1104 where a next network request may be detected. Ingeneral, this method 110 may be repeated indefinitely so long as anendpoint is active or powered on, or so long as the endpoint isconnected to a data network or is otherwise generating network requests.

According to the foregoing, there is disclosed herein a system forverifying user presence associated with network flows. In one aspect,the system may include a network device including a network interfaceconfigured to couple in a communicating relationship with a data networkthat includes an endpoint, a memory on the network device, and aprocessor on the network device. The processor may be configured toexecute instructions stored in the memory to perform the steps ofconnecting an endpoint to the network device through the networkinterface, detecting a network request by a process executing on theendpoint to a remote resource that presents a potential security risk,evaluating a status of the endpoint to determine whether a user ispresent at the endpoint, and executing a security measure in response tothe network request when no user is detected at the endpoint. Thenetwork device may be any physical or virtual network device includingwithout limitation a firewall, a gateway, a threat management facility,or the like.

In complementary fashion, a system may include an endpoint configured toprovide information about user present to such a network device, forexample, by including user presence information in a secure heartbeat orother communication to the network device. In one aspect, the system mayinclude an endpoint including a network interface configured to couplethe endpoint in a communicating relationship with a data network, amemory on the endpoint, and a processor on the endpoint. The processormay be configured to execute instructions stored in the memory toperform the steps of monitoring a status of the endpoint, periodicallycreating a status indicator characterizing the status, generating a userpresence indicator containing an indication of whether a human user ispresent at the endpoint, creating a heartbeat containing the statusindicator and the user presence indicator, and transmitting theheartbeat through the network interface to a gateway that couples theendpoint to a data network.

FIG. 12 shows a method for mitigating distributed denial of serviceattacks from an enterprise network.

In general, a distributed denial of service (DDoS) attack is acoordinated network attack using malicious bots that are installed on alarge number of computers throughout a network and then concurrentlylaunched to flood a target website with requests. As described herein,when a potential trigger for a DDoS attack is followed by an increase innetwork traffic from the endpoint to a high reputation network address,the endpoint is treated as a DDoS service bot and isolated from thenetwork until remediation can be performed.

As shown in step 1202, the method 1200 may include monitoring outboundtraffic from an endpoint in an enterprise network. The endpoint and theenterprise network may in general be any of the endpoints and enterprisenetworks described herein. In general, the method 1200 may be performedby a gateway or threat management facility for an enterprise network, orby an endpoint within the enterprise network, or some combination ofthis. Thus, for example, monitoring may include monitoring outboundtraffic at a gateway for the enterprise network, or monitoring mayinclude monitoring the outbound traffic includes monitoring the outboundtraffic at the endpoint.

As shown in step 1204, the method 1200 may include detecting a potentialtrigger event for a distributed denial of service attack, e.g.,detecting a potential anti-sandbox operation. For example, this may be atrigger event on the endpoint. In an aspect, the detected operation(e.g., the trigger event) may be specific to detecting a processmonitoring clock and wall time drift. In this manner, the potentialtrigger event may be a detection of a process on the endpoint thatmonitors a clock, e.g., by periodically checking a system clock or aremote clock, or by creating and monitoring an internal timer or thelike. The potential trigger event may also or instead be a detection ofa process on the endpoint that monitors a file on the endpoint. Forexample, a launch instruction for a DDoS attack may be encoded in aninnocent looking file that is maintained on an endpoint and updated withan instruction to launch by some other process or the like. This type ofarrangement can obfuscate the presence of the infection and the launchinstruction by permitting control of the DDoS service bot via a simpletext file or other configuration file on the infected machine. Inanother aspect, the potential trigger event may be a receipt of acommunication on the endpoint from a low reputation network address, ora receipt of a message from a (known or suspected) command and controlsite. The message in this context may thus include detecting networktraffic, either directly or through an intermediary, between theendpoint and the low reputation network address, or from a known,suspected, or inferred command and control site. Thus, the potentialtrigger event may be a detection of network traffic between the endpointand a low reputation network address, and/or the potential trigger eventis a detection of network traffic from a command and control site.

In another aspect, the potential trigger event may be access to apublicly available communication channel, such as a group online chat(e.g., chat boards, internet relay chat (IRC), group instant message(IM), etc.) While these types of trigger events may be monitoreddirectly on an endpoint, trigger events may also or instead occur atlocations other than the endpoint. Thus for example, the potentialtrigger event may include a detection of an increase in network trafficto a high reputation network address from one or more other endpoints inthe enterprise network. Where, for example, this is known to beassociated with a software update or the like, the event may be usefullyfiltered. However, where this increase in traffic is very large andspecifically targeted at a particular domain or address, then there is ahigh likelihood that a DDoS attack is being initiated from deviceswithin the enterprise network.

In one aspect, a conviction of a potential triggering event may bereached after aggregating small, suspicious activities over time, suchas repeated contact to remote sites with unknown reputation coupled touse of a local, low-reputation process. This may include any of thetechniques described herein for tracking, e.g., exposure of processes orfiles, use of low-reputation applications, processes, or websites, andso forth. In another aspect, this may include coloring a process as aclock watching process, e.g., using the techniques above, so that arelationship of the process with other processes and objects can bemonitored over time. Similarly, a process that continuously checks for afile that is not present, or otherwise performs a repetitive read,search, file access or the like may be colored as a potential DDoSservice bot. Other suspicious activity that might contribute to amulti-factor detection may include, for example, use of unattendednetwork connections (e.g., connections without any correspondingkeyboard or mouse activity), or use of IP addresses or ports that aretypically reserved for interactive or support connections.

As shown in step 1206, the method 1200 may include observing an increasein network traffic from the endpoint directed to a high reputationnetwork address after detecting the potential trigger event. While it isconceptually possible to launch a DDoS attack on low-reputationwebsites, a malicious attack of this type is typically directed toward aprominent business or website having a well-established and goodreputation. This may, for example, include observing an increase innetwork traffic beyond a predetermined threshold, which may, for examplebe specified in terms of number of requests, number of outbound packets,or any other suitable objective measure for an amount of networkcommunications. This latter technique may be particularly helpful fordistinguishing malicious activity from legitimate activity such asincreased traffic at an ecommerce site due to a sale or promotion, orincreased traffic at a software vendor site due to a security update orother scheduled or newly released software update.

In some implementations, the potential triggering event(s) or anobservation of an increase in network traffic may take place on anetwork device, such as a firewall or gateway. The network device mayobserve the triggering event if the event involves network activity. Thenetwork device may be able to observe that multiple devices are involvedin the triggering event or increased traffic. For example, the activityof one or more endpoints communicating with a low reputation sitefollowed by an increase in network activity by those same endpoints maybe indicative of compromise.

As shown in step 1208, the method 1200 may include, in response to theincrease in network traffic, identifying the endpoint as having acompromised state in which the endpoint serves as a distributed denialof service bot for the distributed denial of service attack.

As shown in step 1210, the method 1200 may include preventing networktraffic from the endpoint until the compromised state is remediated.This may include preventing all network traffic, or only preventingnetwork traffic directed to the network address that is being attacked.More generally, any technique for isolating the endpoint or otherwisepreventing or inhibiting the endpoint from participating in the attackmay be usefully employed in step 1210 to reduce or prevent attacks fromoriginating within the enterprise network.

As shown in step 1212, the method 1200 may include remediating theendpoint. This may include any suitable techniques for removing the DDoSservice bot, or removing or repairing corresponding infections ofotherwise legitimate software executing on the endpoint. After theendpoint has been remediated, the endpoint may return to normal networkcommunications, including legitimate use of the high-reputation networkaddress that was subjected to the DDoS attack.

In one aspect, there is disclosed herein a threat management facilityfor managing an enterprise network. The threat management facility maygenerally include a network interface for coupling the threat managementfacility to the enterprise network, a memory, and a processor. Theprocessor may be configured by computer executable code stored in thememory to protect against a distributed denial of service attackoriginating from within the enterprise network by performing the stepsof monitoring outbound traffic from an endpoint in the enterprisenetwork, detecting a potential trigger event on the network for adistributed denial of service attack, observing an increase in networktraffic from the endpoint directed to a high reputation network addressafter detecting the potential trigger event, in response to the increasein network traffic, identifying the endpoint as having a compromisedstate wherein the endpoint serves as a distributed denial of servicebot, and preventing network traffic from the endpoint until thecompromised state is remediated. The processor may be further configuredto initiate a remediation of the endpoint using any suitable remediationtechniques.

FIG. 13 shows a method for detecting endpoint compromise based onnetwork usage history. In general, most applications will communicate toeither a handful of URL's (e.g., for updates or access to remote data,file servers, mail servers, and so forth) or to hundreds or thousands ofURLs (e.g., for a browser). This bifurcation of the connection historyis useful and knowable at a per-user or per-device level, andapplication level and can be combined with an applications reputationscore and the URL reputation score to better identify if a specific asyet un-classified URL should be considered malicious, suspect or benign.Thus, in the context of network activity by an endpoint in an enterprisenetwork, malware detection can be improved by using a combination ofreputation information for a network address that is accessed by theendpoint with reputation information for an application on the endpointthat is accessing the network address. This information, when combinedwith a network usage history for the application, provides improveddifferentiation between malicious network activity and legitimate,user-initiated network activity. The following method exploits thismulti-factor technique. In general, the following method 1300 may beinstantiated on an endpoint, on a threat management facility or gatewayfor an enterprise network used by the endpoint, or some combination ofthese.

As shown in step 1302, the method 1300 may include detecting aconnection from an application executing on an endpoint in theenterprise network to a network address outside the enterprise network.In general, this may be any communication, interactive session, or thelike that involves a network connection between the endpoint and thenetwork address.

As shown in step 1304, the method 1300 may include determining areputation of the application using the connection. This may include,for example, dynamically evaluating a reputation of the application,e.g., using application coloring or other techniques as describedherein. This may also or instead include using a reputation lookup atthe threat management facility (e.g., where the method 1300 is performedby the threat management facility) or requesting the reputation from thethreat management facility (e.g., where the method 1300 is performed byan endpoint). In another aspect, this may include using a reputationlookup in a local reputation cache maintained on the endpoint, orretrieving reputation information from a local reputation cache on theendpoint to a threat management facility. In general, any suitablemethod for characterizing reputation may be used. For example, anydiscrete or continuous method for characterizing reputation may be used.For example, the reputation may be expressed as a reputation score, orthe reputation may be expressed as a category such as by specifying areputation as one of known malicious, suspect, unknown, or known good.In one aspect, the reputation for the network address may be based oninformation from other devices about the network address, which may beaccumulated, for example, at the threat management facility or any othernetwork resource that receives periodic reporting of reputationinformation for network addresses and aggregates reported informationinto a reputation score or category. In another aspect, reputation maybe established hierarchically, e.g., on a per-user basis, a globalbasis, or some intermediate basis such as for a group of users or acorporate entity, where patterns of usage might be expected to be fairlyconsistent or predictable.

As shown in step 1306, the method 1300 may include determining areputation of the network address accessed by the endpoint through theconnection. A variety of techniques may be employed to evaluate thereputation of the network address. For example, this may include using areputation lookup at the threat management facility (e.g., where themethod 1300 is performed by the threat management facility) orrequesting the reputation from the threat management facility (e.g.,where the method 1300 is performed by an endpoint). In another aspect,this may include using a reputation lookup in a local reputation cachemaintained on the endpoint or on another local network device, such as afirewall, shared drive, etc.

As shown in step 1308, the method 1300 may include determining a networkusage history for the application. This may be based on a monitoredhistory of network activity, for example, by using a log of networkactivity maintained on the endpoint. Thus in one aspect, the method 1300may include retrieving a network usage history for an application byretrieving the network usage history from a log on the endpoint. Thismay also include monitoring network activity by the application andstoring the network usage history for the application in the log forsubsequent use. In general, the log of network activity may be updatedconcurrently with the malware detection process contemplated herein.Thus for example, where a service on the endpoint uses the networkaddress, the log may be updated accordingly based on an inferredrelationship between the service and the application. More specifically,the method 1300 may include associating a network communication to thenetwork address by a service executing on the endpoint with theapplication when the application controls the network communication, andadding the network communication to the network usage history for theapplication.

The history of network activity may also be categorized in any usefulmanner. For example, a particular application may have a predictablepattern of usage, for example, where the application only communicateswith a specific, small group of URLs, or appears otherwise limited inthe number and type of URLs, ports, etc. In this case, the applicationmay be associated with that general pattern of usage, which may beassociated with the particular application on a particular device, orall users of the application across an enterprise. This pattern may beused as a condensed representation of the history of usage in order toavoid a necessity of re-analyzing the complete usage history each timean application reputation is evaluated.

As shown in step 1310, the method 1300 may include evaluating theendpoint for a compromised condition based on the reputation of theapplication, the reputation of the network address, and the networkusage history for the application.

As shown in step 1312, the method 1300 may include remediating theendpoint or initiating a remediating action on the endpoint when acompromised condition is detected.

The method 1300 described above may be instantiated on a threatmanagement facility. Thus in one aspect there is disclosed herein athreat management facility for managing an enterprise network, thethreat management facility comprising a network interface for couplingthe threat management facility to the enterprise network, a memory, anda processor. The processor may be configured by computer executable codestored in the memory to protect against malicious network activity inthe enterprise network by performing the steps of detecting a connectionfrom an endpoint in an enterprise network to a network address,determining a reputation of an application using the connection,determining a reputation of the network address, determining a networkusage history for the application, evaluating the endpoint for acompromised condition based on the reputation of the application, thereputation of the network address, and the network usage history for theapplication, and initiating remediation action on the endpoint when thecompromised condition is detected. In this threat management facility,the reputation of the application may be at least one of knownmalicious, suspect, unknown, or known good, and the reputation of thenetwork address may similarly be at least one of known malicious,suspect, unknown, or known good. The network usage history for theapplication may be retrieved from a log on the endpoint.

FIG. 14 shows useful malware detection insights based on the monitoringdescribed with reference to FIG. 13 . In a variety of circumstances,such as a known bad application contacting a known bad URL, there may beadditional insight that may be obtained from a history of a controllingapplication in combination with other information, such as applicationreputation and URL reputation. Such a combination may serve as the basisfor additional monitoring or the deployment of remedial measures. Insome implementations, an application with a positive reputation thataccesses a URL with a positive reputation may be considered to be anacceptable access even if the new URL has not been accessed by theapplication previously. In other cases, where the application or the URLis unknown or suspect, the access of the URL outside of historical usagemay be suspicious or indicative of compromise. In such cases, theapplication may be investigated or quarantined, the network access ofthe application may be restricted, etc.

In some implementations, an application with a positive reputation thataccesses a new URL with a positive reputation may be suspect if the newURL access is one of multiple new URL accesses (e.g., a number ofaccesses meeting a threshold within a predetermined time window). Forexample, if the new URL involves an increase in network traffic from anendpoint directed to a high reputation network address after a potentialtrigger event, the traffic may be suspect or indicative of compromise.The access of a new URL may be a trigger 1204 (see FIG. 12 ). Forexample, more than a number (e.g., 3, 5, 10) of new URL accesses withina certain time period (e.g., a minute, hour, day, or week, etc.) may beindicative of compromise even if the new URL(s) accessed have a positivereputation.

Specifically, the chart 1400 of FIG. 14 shows the correlation betweenapplication reputation 1402, URL (and/or IP address) reputation 1404, ahistory of a controlling application 1406, and insights or conclusionswhen a new IP/URL connection is detected 1408. In a first example 1410shown in the figure, if the reputation of the application is ‘knowngood,’ the reputation of the URL (or IP address) is ‘known malicious,’and the history of a controlling application includes a constrainedusage of the URL (e.g., a new URL not included in a list such that theURL is considered to be outside of the application's historic usage),the insight or conclusion when this new IP/URL connection is detectedmay include that the ‘good’ application appears to have been exploited.In a second example 1420 shown in the figure, if the reputation of theapplication is ‘known good,’ the reputation of the URL (or IP address)is ‘suspect,’ and the history of a controlling application includes aconstrained usage of the URL (e.g., a new URL not included in a listsuch that there is a new URL/IP address usage that is combined with analready suspect URL/IP address), the insight or conclusion when this newIP/URL connection is detected may include an indication of an exploitand probably a confirmed malicious URL/IP address. In a third example1430 shown in the figure, if the reputation of the application is‘suspect,’ the reputation of the URL (or IP address) is ‘unknown,’ andthe history of a controlling application includes a constrained usage ofthe URL (e.g., a new URL not included in a list), the insight orconclusion when this new IP/URL connection is detected may include acontribution to suspicion that there is a possible exploit. In a fourthexample 1440 shown in the figure, if the reputation of the applicationis ‘known good,’ the reputation of the URL (or IP address) is ‘unknown,’and the history of a controlling application includes a constrainedusage of the URL (e.g., a new URL not included in a list), the insightor conclusion when this new IP/URL connection is detected may includethat the ‘good’ application is going to a new location, but that thislooks suspect. In a fifth example 1450 shown in the figure, if thereputation of the application is ‘known good,’ the reputation of the URL(or IP address) is ‘known good,’ and the history of a controllingapplication includes a constrained usage of the URL (e.g., a new URL notincluded in a list), the insight or conclusion when this new IP/URLconnection is detected may include that the strange activity looks likea good application going to a new good location, e.g., good activity.

It should also be appreciated that the foregoing techniques may beusefully adapted for improved detection of malicious command and controlactivity from unknown network addresses, e.g., even when there is noreputation information available. Command and control IP addresses anddomains are constantly being moved by malicious actors in order to avoiddetection and remain active following discovery. For an unknown URL,aspects of the corresponding outbound or inbound packet communicatedover the network connection may also be inspected instead of or inaddition to the techniques described above, for example to determinewhether the packet pattern, packet shape, packet size, header, payloadprofile, or other characteristics match a known command and controlformat. This latter combination—an unknown network address andpattern-matching to a known command and control packetcharacteristic—may also have independent diagnostic significance. Thatis, this combination may be useful for detection of an advancedpersistent threat in combination with the foregoing methods or as anindependent detection rule or technique.

For example, when an application communicates to command and control itis likely that the first few hundred packets sent are similar to othermalicious communications sent to other addresses used by the attacker,or over different communication ports. If the command and controlsoftware is more stable than the infection malware—that is, the remotecontrol software remains consistent even as the distributed maliciouscode changes, then it may be possible to detect command and controlhandshake and data exchange even when the packets are encrypted.

FIG. 15 shows a method for local proxy detection. Protocol suites suchas hypertext transfer protocol (HTTP) using secure socket layer (SSL)can facilitate secure network communications. In some instances, localproxies may be maliciously installed on an endpoint to support aso-called man-in-the-browser attack or other similar exploit in whichthe proxy intercepts these secure communications, steals a session keyfor communications, and then decrypts what are assumed to be securecommunications with the remote resource for malicious use. For thesecure communication protocols, network addresses are typicallyexpressed as numeric internet protocol addresses rather than thehuman-readable uniform resource locators (URLs) that a user might enterinto a browser address bar, e.g., during typical unsecure networkbrowsing. This property can be exploited to differentiate between secureand insecure communications, and to detect certain instances where amalicious proxy has been deployed to intercept network traffic with anendpoint.

As shown in step 1502, a method 1500 for malicious proxy detection mayinclude monitoring outbound traffic from an endpoint in an enterprisenetwork. The outbound traffic may, for example, include communicationswith remote network addresses outside the enterprise network. Othermalware detection techniques may also or instead be employed alongsidethe local proxy detection contemplated herein. Thus monitoring networktraffic may usefully include looking up a reputation for destinations ofoutbound communications and/or monitoring outbound traffic at a gatewayfor the enterprise network.

As shown in step 1504, the method 1500 may include detecting use of asecure communication protocol with a request from the endpoint. Therequest may be directed from the endpoint to one of the remote networkaddresses. The secure communication protocol may, for example, includeany protocol for securing communications between an endpoint and aremote resource using a session key or the like. This may, for example,include hypertext transfer protocol using secure socket layer ortransport layer security.

As shown in step 1506, the method 1500 may include identifying aplaintext network address within the request. In a secure communicationprotocol, the network address is typically specified using a numericaddress space such as that specified by IPv4 or IPv6. Thus anyalphanumeric plaintext within the address may provide a useful indicatorof a possible local proxy. Thus the plaintext may generally be anyalphanumeric address other than an internet protocol address consistingof a group of numbers. For example, this may be a uniform resourcelocator specifying a top level domain or other textual address, pathnameor the like.

As shown in step 1508, the method 1500 may include, in response toidentifying a plaintext network address in the request, initiatingremediation of a potentially malicious local proxy on the endpoint. Thismay include deploying a wide range of remediation measures ortechniques. For example, initiating remediation may include quarantiningthe endpoint until the potentially malicious local proxy can be removed.Not all local proxies are malicious, thus initiating remediation mayalso or instead include reversing a malware identification for thepotentially malicious proxy by identifying a non-malicious source of thelocal proxy. In another aspect, initiating remediation may includeverifying the initial malware identification, e.g., by performing thesteps of identifying a process that initiated the request, determining areputation of the process, and then conditionally confirming the malwareidentification by performing the steps of: if the reputation of theprocess is low or unknown, confirming the malware identification, and ifthe reputation of the process is good, confirming the malwareidentification only when a calling process for the process that has alow or unknown reputation.

In another aspect, there is disclosed herein a device for maliciouslocal proxy detection. The device may include a network interface, amemory, and a processor. The processor may be configured by computerexecutable code stored in the memory to perform the steps of monitoringoutbound traffic from an endpoint in an enterprise network, detectinguse of a secure communication protocol with a request from the endpoint,identifying a plaintext network address within the request, and inresponse to identifying a plaintext network address in the request,remediating a potentially malicious local proxy on the endpoint. Ingeneral, the device may be the endpoint that is being monitored, e.g.,where the detection system is locally deployed, or the device may be agateway or threat management facility for the enterprise network, orsome combination of these.

The above systems, devices, methods, processes, and the like may berealized in hardware, software, or any combination of these suitable fora particular application. The hardware may include a general-purposecomputer and/or dedicated computing device. This includes realization inone or more microprocessors, microcontrollers, embeddedmicrocontrollers, programmable digital signal processors or otherprogrammable devices or processing circuitry, along with internal and/orexternal memory. This may also, or instead, include one or moreapplication specific integrated circuits, programmable gate arrays,programmable array logic components, or any other device or devices thatmay be configured to process electronic signals. It will further beappreciated that a realization of the processes or devices describedabove may include computer-executable code created using a structuredprogramming language such as C, an object oriented programming languagesuch as C++, or any other high-level or low-level programming language(including assembly languages, hardware description languages, anddatabase programming languages and technologies) that may be stored,compiled or interpreted to run on one of the above devices, as well asheterogeneous combinations of processors, processor architectures, orcombinations of different hardware and software. In another aspect, themethods may be embodied in systems that perform the steps thereof, andmay be distributed across devices in a number of ways. At the same time,processing may be distributed across devices such as the various systemsdescribed above, or all of the functionality may be integrated into adedicated, standalone device or other hardware. In another aspect, meansfor performing the steps associated with the processes described abovemay include any of the hardware and/or software described above. Allsuch permutations and combinations are intended to fall within the scopeof the present disclosure.

Embodiments disclosed herein may include computer program productscomprising computer-executable code or computer-usable code that, whenexecuting on one or more computing devices, performs any and/or all ofthe steps thereof. The code may be stored in a non-transitory fashion ina computer memory, which may be a memory from which the program executes(such as random access memory associated with a processor), or a storagedevice such as a disk drive, flash memory or any other optical,electromagnetic, magnetic, infrared or other device or combination ofdevices. In another aspect, any of the systems and methods describedabove may be embodied in any suitable transmission or propagation mediumcarrying computer-executable code and/or any inputs or outputs fromsame.

The elements described and depicted herein, including in flow charts andblock diagrams throughout the figures, imply logical boundaries betweenthe elements. However, according to software or hardware engineeringpractices, the depicted elements and the functions thereof may beimplemented on machines through computer executable media having aprocessor capable of executing program instructions stored thereon as amonolithic software structure, as standalone software modules, or asmodules that employ external routines, code, services, and so forth, orany combination of these, and all such implementations may be within thescope of the present disclosure. Examples of such machines may include,but may not be limited to, personal digital assistants, laptops,personal computers, mobile phones, other handheld computing devices,medical equipment, wired or wireless communication devices, transducers,chips, calculators, satellites, tablet PCs, electronic books, gadgets,electronic devices, devices having artificial intelligence, computingdevices, networking equipment, servers, routers and the like.Furthermore, the elements depicted in the flow chart and block diagramsor any other logical component may be implemented on a machine capableof executing program instructions. Thus, while the foregoing drawingsand descriptions set forth functional aspects of the disclosed systems,no particular arrangement of software for implementing these functionalaspects should be inferred from these descriptions unless explicitlystated or otherwise clear from the context. Similarly, it may beappreciated that the various steps identified and described above may bevaried, and that the order of steps may be adapted to particularapplications of the techniques disclosed herein. All such variations andmodifications are intended to fall within the scope of this disclosure.As such, the depiction and/or description of an order for various stepsshould not be understood to require a particular order of execution forthose steps, unless required by a particular application, or explicitlystated or otherwise clear from the context. Absent an explicitindication to the contrary, the disclosed steps may be modified,supplemented, omitted, and/or re-ordered without departing from thescope of this disclosure. Numerous variations, additions, omissions, andother modifications will be apparent to one of ordinary skill in theart. In addition, the order or presentation of method steps in thedescription and drawings above is not intended to require this order ofperforming the recited steps unless a particular order is expresslyrequired or otherwise clear from the context.

The method steps of the implementations described herein are intended toinclude any suitable method of causing such method steps to beperformed, consistent with the patentability of the following claims,unless a different meaning is expressly provided or otherwise clear fromthe context. So for example performing the step of X includes anysuitable method for causing another party such as a remote user, aremote processing resource (e.g., a server or cloud computer) or amachine to perform the step of X. Similarly, performing steps X, Y and Zmay include any method of directing or controlling any combination ofsuch other individuals or resources to perform steps X, Y and Z toobtain the benefit of such steps. Thus method steps of theimplementations described herein are intended to include any suitablemethod of causing one or more other parties or entities to perform thesteps, consistent with the patentability of the following claims, unlessa different meaning is expressly provided or otherwise clear from thecontext. Such parties or entities need not be under the direction orcontrol of any other party or entity, and need not be located within aparticular jurisdiction.

It will be appreciated that the methods and systems described above areset forth by way of example and not of limitation. Numerous variations,additions, omissions, and other modifications will be apparent to one ofordinary skill in the art. In addition, the order or presentation ofmethod steps in the description and drawings above is not intended torequire this order of performing the recited steps unless a particularorder is expressly required or otherwise clear from the context. Thus,while particular embodiments have been shown and described, it will beapparent to those skilled in the art that various changes andmodifications in form and details may be made therein without departingfrom the spirit and scope of this disclosure and are intended to form apart of the invention as defined by the following claims, which are tobe interpreted in the broadest sense allowable by law.

What is claimed is:
 1. A computer program product for protecting againstdistributed denial of service attacks from an enterprise network, thecomputer program product comprising computer executable code embodied ina non-transitory computer readable medium that, when executing on one ormore computing devices, performs the steps of: detecting a potentialtrigger event on an endpoint in the enterprise network for a distributeddenial of service attack; in response to detecting the potential triggerevent, monitoring outbound traffic from the endpoint for an increase innetwork traffic from the endpoint directed to a known, good reputationnetwork address over a predetermined time; in response to the potentialtrigger event followed by the increase in network traffic over thepredetermined time, identifying the endpoint as having a compromisedstate in which the endpoint serves as a distributed denial of servicebot for the distributed denial of service attack; and preventing allnetwork traffic from the endpoint to the known, good reputation networkaddress until the compromised state is remediated.
 2. The computerprogram product of claim 1, wherein the potential trigger event is adetection of a process on the endpoint that monitors a clock.
 3. Thecomputer program product of claim 1, wherein the potential trigger eventis a detection of a process on the endpoint that monitors a file on theendpoint.
 4. The computer program product of claim 1, wherein thepotential trigger event is a detection of network traffic between theendpoint and a known, bad reputation network address or a networkaddress of unknown reputation.
 5. The computer program product of claim1, wherein the potential trigger event is a detection of network trafficfrom a command and control site.
 6. The computer program product ofclaim 1, wherein the potential trigger event is a detection of anincrease in network traffic to the known, good reputation networkaddress from one or more other endpoints in the enterprise network. 7.The computer program product of claim 1, wherein monitoring the outboundtraffic includes monitoring the outbound traffic at a gateway for theenterprise network.
 8. The computer program product of claim 1, whereinmonitoring the outbound traffic includes monitoring the outbound trafficat the endpoint.
 9. A method, comprising: monitoring outbound trafficfrom an endpoint in an enterprise network; detecting a potential triggerevent for a distributed denial of service attack; in response todetecting the potential trigger event, monitoring the outbound trafficfrom the endpoint for an increase in network traffic from the endpointdirected to a known, good reputation network address over apredetermined time; in response to the potential trigger event followedby the increase in network traffic over the predetermined time,identifying the endpoint as having a compromised state wherein theendpoint serves as a distributed denial of service bot; and preventingall network traffic from the endpoint to the known, good reputationnetwork address until the compromised state is remediated.
 10. Themethod of claim 9, wherein the potential trigger event is a detection ofa process on the endpoint that monitors a clock.
 11. The method of claim9, wherein the potential trigger event is a detection of a process onthe endpoint that monitors a file on the endpoint.
 12. The method ofclaim 9, wherein the potential trigger event is a receipt of a messageon the endpoint from a known, bad reputation network address or anetwork address of unknown reputation.
 13. The method of claim 9,wherein the potential trigger event is a receipt of a message on theendpoint from a command and control site.
 14. The method of claim 9,wherein the potential trigger event is a detection of an increase innetwork traffic to the known, good reputation network address from oneor more other endpoints in the enterprise network.
 15. The method ofclaim 9, wherein monitoring the outbound traffic includes monitoring theoutbound traffic at a gateway for the enterprise network.
 16. The methodof claim 9, wherein monitoring the outbound traffic includes monitoringthe outbound traffic at the endpoint.
 17. The method of claim 9, whereinmonitoring for an increase in network traffic includes monitoring for anincrease in network traffic beyond a predetermined threshold.
 18. Themethod of claim 9, further comprising remediating the endpoint.
 19. Athreat management facility for managing an enterprise network, thethreat management facility comprising: a network interface for couplingthe threat management facility to the enterprise network; a memory; anda processor, the processor configured by computer executable code storedin the memory to protect against a distributed denial of service attackoccurring within the enterprise network by performing the steps ofmonitoring outbound traffic from an endpoint in the enterprise network,detecting a potential trigger event on the enterprise network for adistributed denial of service attack, in response to detecting thepotential trigger event, monitoring the outbound traffic from theendpoint for an increase in network traffic from the endpoint directedto a known, good reputation network address over a predetermined time,in response to the potential trigger event followed by the increase innetwork traffic over the predetermined time, identifying the endpoint ashaving a compromised state wherein the endpoint serves as a distributeddenial of service bot, and preventing network traffic from the endpointuntil the compromised state is remediated.
 20. The threat managementfacility of claim 19, wherein the processor is further configured toinitiate a remediation of the endpoint.